Library and Information Science

Citations contained in the journals of six fields in science and engineering were investigated. The six fields were: mathematics, physics, chemistry, chemical engineering, electrical and electronics engineering, and mechanical engineering. Source journals of citations were selected in each field on the basis of our previous study. Items of this study were, 1) the form of the cited literature, i. e. journals, books, conference materials, technical reports, patents and others, 2) the special type of cited literature appropriate to each field, e. g. preprints in physics, society papers in mechanical engineering, 3) the age of the cited literature, 4) the fields to which the cited literature belongs. The main findings were: a) in general, there are obvious differences in many items between science and engineering, e. g. journal articles are cited more by scientific journals than by engineering jornals, however, conference materials and technical reports are cited more by engineering journals than by scientific jornals. A large percentage of journal articles cited by scientific journals is published in the same field, while many journal articles cited by engineering journals are published in other fields. However, b) there is some difference in the use of citations both among the three scientific fields and among the three engineering fields, e. g. the proportion of books to all the citations by mathematics journals is the largest in the six fields; the citations by physics journals is the youngest; and the proportion of journal articles cited by mechanical engineering to the all citations by the same field is very small.