McGlone, V.Andrew; Jordan, Robert B.; Martinsen, Paul J. (2002-06-01). "Vis/NIR estimation at harvest of pre- and post-storage quality indices for 'Royal Gala' apple". Postharvest Biology and Technology. 25 (2): 135–144. doi:10.1016/S0925-5214(01)00180-6. ISSN0925-5214.
McGlone, V.Andrew; Jordan, Robert B.; Martinsen, Paul J. (2002-06-01). "Vis/NIR estimation at harvest of pre- and post-storage quality indices for 'Royal Gala' apple". Postharvest Biology and Technology. 25 (2): 135–144. doi:10.1016/S0925-5214(01)00180-6. ISSN0925-5214.