Texture of the zona pellucida of the mature pig oocyte. The mammalian egg envelope revisited Jacques E. Fléchon, Vaclav Kopecny, Juraj Pivko, Antonin Pavlok and Jan MotlikReprod. Nutr. Dev., 44 3 (2004) 207-218DOI: https://doi.org/10.1051/rnd:2004026