1. Cuprak, L. J., and R. L. Stahl. 1973. Modification of plastic culture dishes for single cell observations. J. Maine Med. Assoc. 64:146?149 and 151.
2. Sanford, K. K., W. R. Earle, V. J. Evans, H. K. Waltz and J. E. Shannon. 1951. The measurement of proliferation in tissue culture by enumeration of cell nuclei. J. Nat. Cancer Inst. 11:773?797
3. Personal communication: Mr. David Schneider, Data Packaging Corp., Cambridge, Mass.