Butac, A. M., Roa, Y. M. C., & Serina, C. P. (2001). A methods study on Maple Leaf Enterprises. College of Engineering.
Chicago-viite (17. p.)Butac, Aleczar Monis, Yonnah Marie Caparas Roa, ja Carmela Patricia Serina. A Methods Study on Maple Leaf Enterprises. Diliman, Quezon City: College of Engineering, 2001.
MLA-viite (9. p.)Butac, Aleczar Monis, et al. A Methods Study on Maple Leaf Enterprises. College of Engineering, 2001.
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