Renz M
Nucleic Acids Res. 1979 Jun 25;6(8):2761-7. doi: 10.1093/nar/6.8.2761.
Evidence is presented that the 250 A thick chromosome fiber consists of clusters of nucleosomes (superbeads) which are heterogeneous in size. In bovine lymphocyte chromatin their number average corresponds to about 12 nucleosomes.