Lobov, A.; Babkina, I.; Maltseva, A.; Mikhailova, N.; Granovitch, A. Proteins of Penial Mamilliform Glands in Closely Related <em>Littorina< em> Species (Mollusca, Caenogastropoda): Variability and Possible Contribution to Reproductive Isolation. BioComm 2020, 65, 200–212.