1. A rapid critical point method using fluorocarbons (“Freons”) as intermediate and transitional fluids;Cohen;J. Microsc. (Paris),1968
2. The use of the scanning reflection electron microscope in the study of plant and microbial material;Echlin;J.R. Microsc. Soc.,1968
3. An Introduction to Pollen Analysis. Chronica Botanica;Erdtman,1943
4. The acetolysis method;Erdtman;Sven. Bot. Tidskr.,1960
5. Pollen and Spore Morphology, 3. Plant Taxonomy;Erdtman,1965