I would be grateful if anyone could recommend a good paper (or more than one!) mentioning absolute values of sperm speed. I don't mind which species as I'm trying to put together an overview, but information on mammalian sperm is particularly welcome. There's an awful lot out there on comparative motility, but few papers mentioning absolute values of sperm velocity - or perhaps I've just missed them! If anyone has any recommendations, they'd be gratefully received. Thank you.