1. BELKIN, D.A., FEDERATION PROCEEDINGS 22: 634 (1963).
2. BELKIN, D.A., PHYSIOLOGIST 5: 105 (1962).
3. CHOI, J.K., FINE STRUCTURE OF URINARY BLADDER OF TOAD, BUFO MARINUS, JOURNAL OF CELL BIOLOGY 16: 53 (1963).
4. DUNSON, W. A., AMERICAN ZOOLOGIST 4: 390 (1964).
5. DUNSON, W.A., HERPETOLOGICA 16: 277 (1960).