pennak, R. W. (1953). Fresh-water invertibrates of the United States. Ronlad Press Co.
Chicago Style (17th ed.) Citationpennak, Robert William. Fresh-water Invertibrates of the United States. New York: Ronlad Press Co, 1953.
MLA (9th ed.) Citationpennak, Robert William. Fresh-water Invertibrates of the United States. Ronlad Press Co, 1953.
Warning: These citations may not always be 100% accurate.