1. Cleavage of DNA in nuclei and chromatin with staphylococcal nuclease;Axel;Biochemistry,1975
2. The units of DNA replication in Drosophila melanogaster chromosomes;Blumenthal,1973
3. Replication of DNA in the chromosomes of eukaryotes;Callan,1972
4. Electron microscopy of defined lengths of chromatin;Finch,1975