Simultaneous Spectrophotometric Determination of Lycopene and Beta-Carotene Concentrations in Carotenoid Mixtures of the Extracts from Tomatoes, Papaya and Orange Juice: Lycopene and ?-Carotene Determination. Pakistan Journal of Scientific & Industrial Research. 2013;56(2):90-97. doi:10.52763/PJSIR.BIOL.SCI.56.2.2013.90.97