1. Biosystematic studies in Aster. I. Crossing relationships in the Heterophylli;Avers;Amer. Jour. Bot.,1953a
2. Biosystematic studies in Aster. II. Isolating mechanisms and some phylogenetic considerations;Avers;Evol.,1953b
3. Chromosome behavior in fertile triploid Aster hybrids;Avers;Genetics,1954
4. Clausen , J. D. D. Keck W. M. Hiesey 1940 Experimental studies on the nature of species. I. Effect of varied environment on western North American plants Carnegie Inst. Wash. Pub. 520
5. Interspecific hybrids in Crepis. III. Constant fertile forms containing chromosomes derived from two species;Collins;Genetics,1929