@book{167302,
	author = {Constantino Pérez, Rolando},
	title = {Sincronización de estros en vaquillas Holstein tratadas con Norgestomet + PGF2a y Norgestomet + E2  /},
	publisher = {El autor,},
	year = {2002},
	address = {Chapingo, Méx.  :}
}