Detrimental effects of non-functional spermatozoa on the freezability of functional spermatozoa from boar ejaculate - Martínez-Alborcia, María José; Valverde-Abarca, Anthony; Parrilla, Inmaculada; Vázquez, Juan M.; Martínez, Emilio A.; Roca, Jordi (PLOS One, 2012)