The purpose of this study was to examine factors which may explain frequency and nature of use of documents in citing document texts over time. Articles published in the Journal of the American Society for Information Science in 1972, 1973, and 1974 were searched on SciSearch to derive two sample groups. One group was frequently cited; the other was infrequently cited. The functional uses of the sample document groups were examined by four classification taxonomies in 417 citing contexts. The patterns of frequency of use, multiple use, and functional use were examined over time. The citation levels of documents citing the two sample groups were examined as well. When measured by functional citation taxonomies, frequently and infrequently cited documents were not used for significantly different functions. Frequently cited documents, however, seemed more tightly linked (essential) than infrequently cited documents to the documents in which they were used. While frequently cited documents were not judged more useful than infrequently cited documents initially, they were used at a stable higher level over a longer period. Infrequently cited documents were used immediately following publication and then their use rapidly diminished. The repeated use of infrequently cited documents within documents tended to decrease over time while the repeated use of frequently cited documents tended to increase. Frequently cited articles were used for different functions in the period immediately following publication and a later time period. Infrequently cited articles were used with greater consistency in the two time periods.