1. Timing of the phases of the cell cycle during the period of asynchronous division up to the 49-cell stage in Lymnaea;Biggelaar;J. Embryol. Exp. Morphol,1971
2. Development of dorsoventral polarity preceding the formation of the mesentoblast in Lymnaea stagnalis;Biggelaar,1976
3. The fate of maternal RNA containing ectosomes in relation to the appearance of dorsoventrality in the pond snail, Lymnaea stagnalis;Biggelaar,1976
4. Development of dorsoventrality and mesentoblast determination in Patella vulgata;Biggelaar;J. Morphol,1977
5. Experimental studies on germinal localization in Ilyanassa. I. The role of the polar lobe in determination of the cleavage pattern and its influence in later development;Clement;J. Exp. Zool,1952