Grassmé, H., Gulbins, E., Brenner, B., Ferlinz, K., Sandhoff, K., Harzer, K., et al. (1997). Acidic sphingomyelinase mediates entry of N-gonorrhoeae into nonphagocytic cells. Cell, 91(5), 605-615. doi:10.1016/S0092-8674(00)80448-1.