1. The genus Crepis. Part one: The taxonomy, phylogeny, distribution and evolution of Crepis.;Babcock;Univ. Calif. Publ. Botan.,1947a
2. The genus Crepis. Part two: Systematic treatment.;Babcock;Univ. Calif. Publ. Bot.,1947b
3. Chromosomes and phylogeny in Crepis III. The relationships of one hundred and thirteen species.;Babcock;Univ. Calif. Publ. Bot.,1943
4. The chromosomes and relationship of Crepis suriaca (Bornm.).;Cameron;Univ. Calif. Public. Agricult. Scienc.,1934