LIfERA TURE SEARCHING WITH THE SCIENCECITATION INDEX: AN EXPERIMENTAL STUDY*

The retrieval efficiency of the 'Science Citation'Index' is tested in respect of the Indian references ona very specific area of bio-medical research, namely'Haemorrhagic Fevers'. The procedure followed.results obtained and conclusions drawn thereupon arepresented.

SCIENCE CITATION INDEX

Of the several citation indexes. "probabiythe best known, certainly the most widelypublicized" {l] one is the 'Science CitationIndex' [he r-einafte r referred to SCI) which isbeing brought out by the Institute for ScientificInformation, Philadelphia, Pa. sinceNovemb or 1963. It represents .orie (,f thefirst r' , Jor attempts to provide the scientificcornr lity with a multidisciplinary index tothe ~rgrowing mass of literature [2]. ThisIa r v.'. effort has been the work of a pioneerin.ne field, Dr. Eugene Gearfield. A detaileddc scr ipt ion of the various sections of the SCI,i;s frequency, coverage, search strategy,3.pplications, etc. have been publishedelsewhere [3,4,5,6]. The advantages anddisadvantages of using the SCI as a subjectsearching tool have also been discussed bySpencer [7].

2 PURPOSE OF THE PRESENT STUDY

The basic objective of thi.s study is toevaluate the usefulness of the SCI as a searchtool in retrieving literature concerning a veryspecific area of bio-medical research.

3 PROCEDURE FOLLOWED

The evaluation of the SCI was accom-plished by compari.ng the entries listed underthe specified heading of an already compiled.conventional subject bi.bliography with thoseobtained from the SCl.

J S GHOSH

D irec torate of R es e arc b Coordination

and Industrial Liaison. Neu. Delbi-l

31 Conventional Subject Bibliography

The publication chosen for the purposeof the test is entitled "Work done in Indiaon Viral and Rickettsial Infections ofVertebrates - a Bibliography" {hereinafterreferred to as BIB which has been broughtout by the Indian National Scientific Docu-mentation Centre, New Delhi, India in 1967[8]. The entire work of the compilation,"except in a exceedingly few cases ", isbased on the actual verification of the originalsources. The entries of the BIB are classi-fied according to the scheme worked out bySir Christopher Andrews in his classicalwork "Viruses of Vertebrates" [9]. The BIBenli sc s a total number of 3, 267 entries whichare arranged chronologically under specificsubject headings. The "Medical SubjectHeadi.ngs II list published by the U. S. NationalLibrary of Medicine {l0] was consulted inassigning the subject headings and preparingthe Subject Index to the entries of the BIB.

32 Selection of the Subject

The subject that was chosen for thepurpose of testing the SCI was the Haemorrha-gic Fevers (Synonym: Haemorrhagicnephritis) (hereinafter referred to as HF).The criteria for selecting this subject wereas follows:

1. The subject was extremely specific;

2. It was comparatively recent whichposed a new but serious problemin India and elsewhere as well asstimulated further attention beingpaid to this otherwise benigndisease;

3. Investigations in considerable detailand with acceptable significancehave been carried out in India and anumber of paper s have been pub-lished by Indian researchers on

*- Based on a Pro jec: Report submitted to INSDOC as a part 01 its 1raining Course inDocumentation and Reprograpby during 1966-67.

Vol 14 No 3 September 1967 133

this topic. This would, in turn,imply the probability of theircitation in the works of the sub-sequent inv e stigator s which wouldultimately mean their appearancein the SCI.

33 Collecting the References from the BIB

There were as many as twelve refer-ences (as shown in Annexure I) cited underthe heading 'Miscellaneous Arboviruses _Haemorrhagic Fevers'. All these entrieswere recorded on individual slips of 5 x 3 inchsize, designated in this article as 'processslips'. with their full bibliographic details.

These slips were kept arranged first by yearof publication and then alphabetically accord-ing to author, within any particular year.

34 Searching the SCI

The 1964 and 1965 editions of the SCIwere utili sed for the purpose of the search.It may. however, be made clear here that ouraim to use the SCI was not for compiling anysubject bibliography but primarily to ascertainthe extent of coverage of the host itemsenlisted in the BIB. As such, the testcarried out to determine the soundne s s ofthe SCI as a retrieval tool confined itselfrria in ly to the recording of only the Indian'descendent' papers corresponding to theparticular 'ancestor papers' indexed in theSCI v olurne s , Nevertheless, the additionalcited as well as citing Indian references thatwere collected from the SCI during the searchwere also considered for the purpose ofevaluation.

341 Fir st Step

The papers in the BIB were consideredto have constituted the universe or totality ofwork since the BIB appears to be appreciablycomprehensive in coverage. As a result, itwas not necessary to be very specific aboutthe selection of any particular paper in enter-ing the SCI. Any of the twelve host paper~would serve the purpose of a starting refer-ence since all of the m would ultfmate ly beused in the search-cycle.

The 'target papers' that were coveredin the 'Citation Index' section of the SCI were

134

GHOSH

noted and the bibliographic details of each ofthe 'descendent' papers were recorded in therespective process slips. The references ofthese citing works were looked up in the'Source Index' section of the SCI to locate thetitles in order to assess their possiblepertinence (that is, whether on the subjectproper) as well as relevance (that is, whetherof interest to the specialists in the field).Whenever possible, the pertinence and rele-vance were determined on the basis of occur-rence of such qualifying words as 'Haemar-rhagic Fevers' and 'Dengue', 'ChikungunyaVirus', etc. respectively, in the titlesthemselves. All the pertinent/relevarit'descendent' papers under any particular'ancestor' or 'target' paper became a candi-date for access to the SCI as new startingreference and the process of search was conti-nued in order to conduct a preliminary test onthe percentage of retrieval of reference by theSCI, at every subsequent steps of search. Ifthe possible pertinence/relevance could not bedetermined from the title, the citing referenceswere kept recorded as such in the processslips with asterisk marks to designate themas 'tentatively discarded' Iterns for the ttrnebeing. The 'target' papers that could not belocated in the SCI were also appropriatelynoted.

342 Second Step

In course of the Frist Step of search.all the cited papers by a given first-namedauthor supplied by the SCI, but not included inthe BIB, were recorded on a separate set ofslips along with their corresponding citingreferences. The 'Source Inde x+sect ion of theSc:I was further consulted to ascertain thepertinence/relevance of the se new group of'descendent' papers. The cited items were,however, marked as 'tentatively discarded'since there was no possibility of determining

their pertinence/relevance in the abscence oftitles in the 'Citation Index' section of the SCI.

343 Third Step

All the 'tentatively di scarded' refer-ences so far accumulated were checked in thejournals in which they originally appeared todetermine their pertinence/relevance. Thepertinent/relevant ones were simply recordedand counted but were not "re-inserted" into theSCI since it has already been noted that ouraim was to compare the SCI's coverage of the

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LITERATURE SEARCHING WITH SCIENCE CITATION INDEX

host papers of the BIB and not the preparationof any subject bibliography on HF. For thesame reason, no additional effort was made tocollect more references by the same author sof interest from the 'Source Index' section ofthe SCl.

35 Re-checking the BIB

The additional pertinent/relevant refer-ences that could be retrieved from the SCIwere searched back in the BIB through its'Author Index' in order to ascertain whetherthey are at all included there (that is, in theBIB) and if so, under which subject heading.

The diagram in page 136 illustrates thesearch procedure adopted in this study and thefollow-up in the BIB.

4 PRESENTATION OF DATA

There were a total number of 12 refer-ences' available in the BIB (as in Appendix I),distributed over nine different first-namedauthors. Of these 12 papers, as many as 6or 5010 could be retrieved from the 1964 SCIalone, while 3 other papers or 25% ,wasavailable exclusively in the 1965 SCI. 5 refer-ences (about 42%) were found to be common toboth the 1964 and 1965 SCI, and only 1 paper(about 8.310) was obtained as unique referencefrom the 1964 SCI. As Table 1 indicate s, itwas possible to retrieve 75% of the 12 targetpaper s by referring to both the 1964 and 1965editions of the SCI, having recorded the 5common references against the 1964 SCI.

Table 1: Number and percentage of the articles found in the 1964 and 1965 SCI asagainst the total papers of BIB

S1.Author No. of papers No. of paper s cited Cumulative %

No. in BIB in the SCI total1964 1965 Total

SARKAR J K 4 2 2 2

2 AIKAT B K 3 25

3 CHAUDHURI R N 4

4 DE S N 5

5 KUNDU S C

6 PAVRI K M 6 50

7 RAMAKRISHNAN S P 7

8 RAO T R 8

9 WATTAL B L 9 75

Total: 12 6 3 9 751.

The se data would seem to indicate thatthe retrieval capacity of the SCI (7510), atleast for the Indian references on HF, isappreciably high, considering the fact that theSCI covers only one Indian medical journalnamely, the Indian Journal Medical Researchin its list of "Source Journals".

The 12 papers in the BIB were publishedin three different Indian journals, the break-up of which is as follows:

Vol 14 No 3 September 1967

Indian Journal of MedicalResearch 7 nos.

Bulletin of the Calcutta Schoolof Tropical Medicine 3 nos.

Journal of the IndianMedical Association 2 nos.

Of the 9 paper s that were retrieved by the 1964and 1965 SCI, as many as 7 (about 77.81.)were published in the Indian Journal of Medi(;al

135

GHOSH

Starting referenc es(12 papers in BIB)

.LI Citation Index I

1 1Not cited I Citing papers of I Other works by

in SCI the cited items authors of

1starting

references

INoted I ..L. .1

Citing - Citedpapers papers

I Source Index I Pertinent/ rwith titles I Relevant items

~ Tentatively discarded items

Checking with thehost periodicals

1 1Non -pertinent/ Pertinent/Non -relevant Relevant

, items items

1Discarded I Re-checking with

the BIB

(A diagrammatic representation of the search strategy in the SCI andthe re-checking in the BIB)

136 Ann Lib Sci Doc

LITERATURE SEARCHING WITH SCIENCE CITATION INDEX

Research and the remammg 2 were shared bythe other two journals. This stands to speakvery high of the judicial selection pol icyadopted by the ISI in preparing the "masterlist" of source journals for the SCI.

Now let us analyse the citing paper s thatwere found. to be present under the 'targetpaper s ' cited in the SCI. Having excluded thecommon ones. there were a total number of17 unique citing references which were foundto have cited the 9 papers of the BIB. Of these17 papers. 5 were the host papers that wereincluded in the BIB under the heading 'Haemor-rhagic Fevers' and also covered by the SCI ascited works. Of the remaining 12 references,3 were found to be actually 'on HF' whichwere enlised in the BIB not under the specifiedheading namely. 'Haemorrhagic fevers' butunder "Chikungunya"; 8 that were 'relating toHF' were recorded, in the BIB. under eitherthe heading 'Chikungunya' or 'Dengue '. andthe last one was not at all included in the BIBbut retrieved only through the SCI.

These figure would seem to support theclaim of superiority of concept-orientednessof the SCI over the language-limitedness of aconventional index which results in a scatter-ing of the articles of interest to any group ofresearchers.

Let us now see the rate of productivityof the SCI so far as Indian literature ~relating to HF is concerned. No strictcriterion was however, followed in selectingthe 'starting paper'. After arranging theprocess slips for all the 12 host papers firstby chronology and then alphabetically accord-ing to the surname of the first-named authors,the very first reference was chosen to startwith the search. The process of 'cycling' wasrepeated until any new reference ceased toappear. The test was carried out. better sayto a limited extent, with a view to ascertainingthe soundness or otherwise of the SCI as atool to retrieve the papers of interest, if onlyone paper (preferably a key-paper) in thefield of research. here it is bio-medical, wereknown to the searcher. In the following pro-ducti vity chart, the article s on HF andrelating to HF have been characterized by thesymbols "0" and "R" re spective Iy, while theduplicate or cornmon ones are indicated bynD", Of the articles on HF the on es that areincluded in the BIB under the appropriateheading name 1y. 'Haemorrh!lgic fever s' aremarked with an 'asterisk' while those recordedin the BIB elsewhere namely, 'Chikungunya'

Vol 14 No 3 September 1967

and 'Dengue' are 'double-aster:~ked'. Of thearticles relating to HF, those that are in-cluded in the BIB have been designated by thesymbol + and the 'unique references' by thesymbol x. The journal entitled 'IndianJournal of Medical Research' and 'CurrentScience' have been abbreviated to 'IJMR' and'CS' respectively, and the year 1964 and 1965to '64' and '65' respectively in the followingchart:

Starting Paper

Aikat B K. Konar N R. Banerjee G -Haemorrhagic fever in Calcutta area.IJMR 64, 52. 660-75.

1st runSCI 1964

Pavri K M: IJMR 64.52.692 0Ramakrishna S P: IJMR 64, 5Z. 633 0Rao T R: IJMR 64,52,727 0Shah K V: IJMR 64,52,676 0

SCI 1965

Dandawa t e C N: IJMR 65,53,707Krishnamurthy K: IJMR 65,53,800Sarkar J K: IJMR 65,53,921Thiruvengadam K V: IJMR 65,53,

729

R+R +Rx

R+

2nd run

Starting Paper: Pav r i K M - IJMR 64,52,692

SCI 1964

Pavri K M: IJMR 64,52,698 R +Ramakrishna S P: IJMR 64,52,633 DRao T R: IJMR 64,52.719 R +Rao T R: I.Ji..1R 64,52,727 DShah K V: IJMR 64,52,703 R +

SCI 1965

Anderson C R: CS 65,34.579Jadhav M: IJMR 65,53,764Rao T R: IJMR 65,53,689Sarkar J K: IJMR 65, ')3, 921Singh K R P: CS 65. 34.480

oR+R +Do

3rd run

Starting Paper: Ramakrishna SP - IJMR 64,52,633

SCI 1964

Rao T R: IJMR 64,52,727

SCI 1965

D

Thiruvengadam K V: IJMR 65,53,729 D

137

4th run

Starting Paper: Rao T R - IJMR 64,52,727

SCl1964

Not cited

SCl1965

Krishnamurthy K: IJMR 65,53,800 DPaul S D: IJMR 65,53,777 R +

5th run

Starting Paper: Shah K V - LTMR64,52,676

SC11964

Ramakrishna S P: IJMR 64,52,633 DRao T R: D'MR 64,52,727 DShah K V: D'MR 64,52,703 D

SC11965

Jadhav M: JJMR 65,53,764Myers R M: JJMR 65,53,694Shah K V: JJMR 65,53,610

DR+Rx

6th run

Starting Paper: Dandawate C N: - JJMR 65,53,707

SCI 1965

Tiruvengadam K V: .IJMR 65,53,729

7th run

Starting Paper: Krishnamurthy K - IJMR 65,53,800

SCI 1965

Paul S D: IJMR 65,53,777Paul S D: IJMR 65,53,790

DR+

8th run

Starting Paper: Sarkar:r K - D'MR 65,53,921

SCl1965

Not cited

9th run

Starting Paper: Thiruvengadam K V - IJMR65,53,729

SCI 1965

Myers R M: D'MR 65,53,694 D

10th run

Starting Paper: Pavri K M - IJMR 64,52,698

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GHOSH

SCI 1964

Ramakrishna S P: IJMR 64,'52,633 DRao T R: IJMR 64,52,719 DRao T R: LTMR64,52,727 D

SCI 1965

Banerjee K: D'MR 65,53,715Dandawate C N: JJMR 65,53,707

R+D

lith run

Starting Paper: Ramakrishna S P - D'MR 64,52,633

SCI 1964 and SCI 1965

Same as shown under '3rd run' 'above

12th run

Starting Paper: Rao T R - IJMR 64,52,719

SCl1964

Rao T R: IJMR 64,52,727

SCI 1965

D

Not cited

13th run

Starting Paper: Rao T R - IJMR 64,52,727

SCI 1964 and SCI 1965

Same as shown under '4th run' above

14th run

Starting Paper: Shah K V- JJMR 64,52,703

SCI 1964

Ramakrishna S P: JJMR 64,52,633 DRao T R: LTMR64,52,727 D

SCl1965,

Cited only by a foreign author. Henceno further reference added.

15th run

Starting Paper: Anderson C R - CS 65,34,579

SCl1965

Not cited

16th run

Starting Paper: Jadhav M - LTMR65,53,764

SCI 1965

Myers R M: IJMR 65,53,694 D

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17th run

Starting Paper: Rao T R - LTMR65,53,689

SCI 1965

Dandawate C N: LTMR65,53,707Myers R M: LTMR65,53,694Paul S D: LTMR 65,53,777

18th run

Starting Paper: Sarkar J K - LTMR65,53,921

SCI 1965

Not cited

19th run

Starting Paper: Singh K R P - CS 65, 34,480

SCI 1965

Not cited

20th run

Starting Paper: Rao T R - LTMR64, 52, 727

SCI 1964 and SCI 1965

Same as shown under '4th run' above

21st run

Starting Paper: Thiruvengadam K V - LTMR65,53,729

SCl1965

Same all shown under 9th run' above

22nd run

Starting Paper: Krishnamurthy K - LTMR65,53,800

SCI 1965

Same all shown under '7th run' above

23rd run

Starting Paper: Paul S D - I:rMR 65,53,777

SC11965

Krishnamurthy K: LTMR 65,53,800 DPaul S D: LTMR 65,53,790 D

24th run

Starting Paper: Ramakrishna S P - LTMR64,52,633

SCI 1964 and SCI 1965

Same as shown under '3rd run' above

Vol 14 No 3 September 1967

25th run

Starting Paper: Rao T R - LTMR 64,52,727

SCI 1964 and SCI 1965

DDD

Same as shown under '4th run' above

26th run

Starting Paper: Shah K V - LTMR 64,52,703

SCI 1964 and SCI 1965

Same as shown under '14th run' above

27th run

Starting Paper: Jadhav M - IJMR 65,53,764

SCI 1965

Same as shown under IJ. 6th run' above

28th run

Starting Paper: Myers R M - IJ'MR 65,53,694

SC11965

Dandawate C N: IJMR 65,53,707Jadhav M: LTMR65,53,764De Ranit,; C M: IJMR 65,53,756

DDR+

29th run----Starting Paper: Shah K V - D'MR 65,53,610

SCl1965

Not cited

30th run

Starting Paper: Thiruvengadam K V - IJMR65,53,729

SCI 1965

same as shown under '9th run' above

31st run

Starting Paper: PaulS D - IJMR 65,53,777

SCI 1965

Same as shown under '23rd run' above

32nd run

Starting Paper: Paul S D - LTMR65,53,790

SCI 1965

Krishnamurthy K: LTMR65,53,800 DPaul S D: LTMR65,53,777 D

139

33rd run

Starting Paper: Myers R M - JJMR 65,53,694

SCI 1965

Same as shown under '28th run' above

The data derived from the above 33 runsexcluding the common ones, can be sum-marised as follows:

Table 2: Number of references retrievedfrom the SCI 1964 and SCI 1965during the process of 'cycling'

Item Numbers

(a) Articles on HF and includedin the BIB under the sameheading

Articles on HF and includedin the BIB elsewhere

Articles relating to HF andincluded in the BIB

Articles relating to HF but notincluded in the BIB 2

3

(b)3

( c)13

(d)

Total number of references retrieved 21

The figures presented in Table 3indicates that the percentage of retrieval ofnew references was maximum in the '1st run'(about 38. 110). Thereafter, it starts de-creasing which is but obvious. There wereseveral runs which did not give any newreference at all. It is, however, worthwhile,to mention here that of the 21 references thatcould be retrieved from the SCI, 2 (about9.5'10) papers were unique in the sense thatthey were available only in the SCI and notfound in the BIB.

41 Analysis of Data

In course of search with the SCI, a totalnumber of 65 references (including 4 non-journal items) were obtained through otherpapers of the authors of interest that is, thoseauthors whose works constituted the universeof target papers of the BIB. These 65 refer-ences included works of Indian authors otherthan those of the BIB. Of these 65 references13 were on HF, of which 5 were included inthe BiB ~ HF itself, 6 were included inthe BiB elsewhere, and the remaining 2 were

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GHOSH

T'ab.l e 3· Number and percentage of newreferences retrieved at every step(or run) of the search

Stage ofSearch -cycle

No. of new referencesretrieved

Per-centage

on HF relating Totalto HF

Ist run 42nd run 23rd run4th run5th run6th run7th run8th -9th runs10th run11th -27th runs28th run29th-33rd runs

87

38. 133.3

45

I2

4.89.5

I2

4.8

4.8

4.8

100.0Total 6 15 21

not at all cited in the BIB. On the other hand,of these 65 references, II were found to berelating to HF of which, again, 8 were includedin the BIB under appropriate heading but theremaining 3 were given exclusively by the SCI.Subtracting the se (that is 13 plus 11) from thetotal we had 41 (65 minus 24) in our hand(including 4 non-journal items) which werefound to be absolutely irrelevant (that is,neither pertinent nor relevant to the subject ofsearch). These 41 references account for avery high percentage of 'noise factor' - ashigh as about 63'10 - in the use of the SClas aretrieval tool, at least in the specified fieldof search as mentioned earlier. On the otherhand, the SCI had given a total number of 5unique references which include papers on HFand relating to HF as well. Hence, comparedto these 5 unique references (considering thatthe papers on and relating to HF are equallyimportant), constituting about 8'10 of the totalpapers retrieved, the 'noise' to the extent of63'10 is really something worth noting in theSCI.

5 CONCLUSIONS

A few important points which may befocussed in conclusion are:

1. The rate of productivity is muchhigher in the earlier runs of the SCI searchthan in the latter runs.

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LITERATURE SEARCHING WITH SCIENCE CITATION INDEX

Z. Within the small sample, the retrievalefficiency of the SCI was 75%. This is quitehigh considering the fact that the SCI coversonly one Indian medical periodical as sourcejournal.

3. It is also interesting to note that theSCI retrieved at least Z unique referenceswhich are not covered by a bibliography com-piled after consulting a number of conventionalindexing and abstracting peri.odicals and alsoprimary periodicals.

4. The 'noise factor' of the SCI due toretrieval of non-pertinent and non-relevantreferences was as high as 63'1. in the sample.

REFERENCES

[1] Martyn, J: (An) Examination of citat ionindexe s. Aslib Proceedings 1965,17(6), 184-96.

[Z] Waldhart, T J: (A) Preliminary ana-lysis of the 'Science Citation Index.Thesis. University of Wisconsin,1964

[3] Institute for Scientific Information,Philadelphia, Pav : "What is theSCIENCE CITATION INDEX", 1964.(Advertisement leaflet).

[4] Institute for Scientific Information,Philadelphia, Pa.: Effective use ofthe SCIENCE CITATION INDEX:a programmed text. 1964.

[5] Institute for Scientific Information,Philadelphia, Pa.: Science CitationIndex. (Advertisement leaflet).

[6] Science Citation Index 1965. Vol. 1.Philadelphia, Pa.: Institute for

Scientific Information, 1966.

[7] Spencer, C C: Subject searching withScience Citation Index; Preparationof a drug bibliography using Chemi-cal Abstracts, Index Medicus, andScience Citation Index 1961 and 1964.American Documentation 1967, 18(Z),87 -96.

[8] Indian National Scientific DocumentationCentre, New Delhi, India: Work donein India on Viral and RickettsialInfections of Vertebrates - a Biblio-graphy. New Delhi, the Centre, 1967.

[9] Andrews, C: Viruses of Vertebrates.Williams &< Wilkins, 1964.

Vol 14 No 3 September 1967

[10] U. S. National Library of Medicine:Medical Subject Headings. 3rd edn,Washington, Dept. of Health, Edu-cation and Welfare, 1964. (Pt Z ofIndex Medicus, vol. 5(1) 1964).

Appendix I

List of papers on 'HaemorrhagicFever' collected from the BIB.

Virus Study

Pavri K M, Banerjee G, Anderson C R,Aikat B K: Virological and serologi-cal studies of cases of haemorrhagicfever in Calcutta; Material collectedby the Institute of Post-GraduateMedical Education and Research(IPGME), Calcutta. Indian J medRes 1964, 5Z(7), 69Z-7.

2. Sarkar J K, Chatterjee S N, Cha.kra-varty S K: Virological inve sti.gationon Calcutta haemorrhagic fever.Preliminary report. (Letters). BullCalcutta Sch trop Med 1964, 12, 2-3.

1.

3. Sarkar J K, Chatterjee S N, Chakra-varty S K: Further progress in thestudy of haemorrhagic fever inCalcutta. Bull Calcutta Sch tropMed 1964, lZ, 10Z-3.

4. Sarkar J K, Chatterjee S N, Chakra-Varty S K, Anderson C R: Virologi-cal and serological studie s of case sof haemorrhagic fever in Calcutta.Material collected by the CalcuttaSchool of Tropical Medicine. Indian.} med Res 1964, 5Z(7), 684-91.

5. De S N, Sen S N, Mukherjee S, Ven-katachalam M A: Hepatic necrosiswith haemorrhagic fever. J Indianmed Ass 1964, 4Z(lZ), 557-60(case study).

6. Kundu S C, Mukherjee P K, Bakshi K B:Calcutta haemorrhagic fever, obser-vations on 15 case s. J Indian medAss 1964, 43, 464-9.

141

Epidemiology

7. Aikat B K. Kona r N R. Banerjee G:Haemorrhagic fever in Calcutta area.Indian J med Res 1964. 52(7).660-75. 13 ref.

8. Chaudhuri R N. Chatterjea J B. SahaT K. Chaudhuri A D: Calcuttahaemorrhagic fever. Bull CalcuttaSch trop Med 1964. 12. 1-2.

9 Ramachandra Rao T. Ander son C R:Concluding review on the papers onthe outbreak of febrile illness withhaemorrhagic manife stations inCalcutta. Indian J med Res 1964.52(7). 727-34. 15 ref.

142

GHOSH

10 . Ramakrishnan S P, Gelfand H M. BoseP N. Sehgal P N, Mukherjee R N:Epidemic of acute haemorrhagicfever, Calcutta. 1933: Epidemio-logical inquiry. Indian J med Res1964. 52(7), 633-50. 11 ref.

11 Sarkar J K. Chatterjee S N. Chakra-varty S K: Haemorrhagic fever inCalcutta: Some epidemiologicalobservations. Indian J med Res1964. 52(7). 651-9. 11 ref.

Transmission

12 Wattal B L: Note on Aedes survey ofCalcutta following an outbreak ofhaemorrhagic fever in July 1963.Indian J med Res 1964. 52(7). 710-18.

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