Supply specific geographic information and are often designed for specific areas of research. Kreissman, Bernard . 1991 Mason, Robert J. Atlas of United States Environmental Issues . The Random House Atlas of the Oceans . Random House, 1991.
Legal sources define and explain legal standards within specific subject areas of the law.
California Environmental Laws . The Complete Guide to Environmental Law . William P. Parkin. 2 vols. Federal Environmental Laws . Bergey's Manual of Determinative Bacteriology .