This thesis entails a citation analysis study of selected source journals in the pure andrnapplied sciences, in Ethiopia. The basic aim was to determine the communicationrnpatterns of scientists in Ethiopia through the documents that they cited in the researchrnarticles, over a ten-year period from 1985 to 1994.rnBy employing a selection criteria-based purposive sampling technique, three sourcernjournals were selected namely: Ethiopian Journal of Agricultural Sciences (EJAS);rnEthiopian Medical Journal (EMJ); and SINET: Ethiopian Journal of Sciences (SINET).rnBibliographic data from a total of 4496 citations were processed, analyzed and presentedrnin accordance with the set objectives. dBASE IV, SAS and WordPerfect 5.1 software werernthus used.rnResults obtained, showed that the frequency distribution of the age of cited documents,rnconformed to a type of exponential distribution. It was also found that most of the citedrndocuments (at least 77.34 percent) were published outside Ethiopia, and also at leastrn74.36 percent of the cited documents comprised primly sources of information. Thernmost prolific and most cited authors were determined as well as the most frequentlyrncommunicated subjects in each source journal, respectively.rnUltimately, several suggestions pertaining to the future betterment of the observedrncommunication patterns, were posed. Possible future roles of the local libraries andrninformation centers supporting S & T research activities in Ethiopia were highlighted,rnon the basis of the implications of the communication patterns observed.