This bibliography provides references for each known metallic mineral district in Pima and Santa Cruz Counties in Arizona. In a mineral-district classification, known metallic mineral occurrences are grouped according to geologic and metallogenic criteria rather than the geographic associations used in the traditional mining-district approach (Keith and others, 1983a,b). Ideally, a mineral district should consist of mineral occurrences that have a common genesis. A mineral-district classification is especially useful for understanding the geologic setting of mineralization and the distribution of known mineral occurrences with similar geology. A mineral-district map, however, is by no means a statement of mineral potential because future mineral discoveries within and outside established districts will affect district boundaries. Although understanding the distribution of known mineral deposits is essential in evaluating mineral potential, many other geologic and technologic factors must also be considered (Fellows, 1984). This circular is the third in a series of county-by-county bibliographies for metallic mineral districts in Arizona. This and other circulars are based upon the work of Keith and others (1983c), but provide a more usable format and more comprehensive reference lists than the latter publication. Nearly 1,100 citations are listed in this circular.