Champluvier, B., Kamp, B., & Rouxhet, P. (1988). Preparation and Properties of Beta-galactosidase Confined in Cells of Kluyveromyces Sp. Enzyme and Microbial Technology, 10(10), 611-617. https://doi.org/10.1016/0141-0229(88)90108-1 (Original work published 1988)