Botti, Maddalena, Ferdinando Gazza, Luisa Ragionieri, Luisa Bo Minelli, and Rino Panu. 2013. “Double Labelling Immunohistochemistry on the Sympathetic Trunk Ganglia Neurons Projecting to the Extrinsic Penile Smooth Musculature of the Pig: An Experimental Study on the Retractor Penis Muscle”. Italian Journal of Anatomy and Embryology 118 (2):223-39. https://oajournals.fupress.net/index.php/ijae/article/view/1200.