NII-OKAI, D.; ACHEAMPONG, E.; MAHAMA, I.; MENSAH, J. K.; IMORO, O.; MARFO, R.; KWAW, R.; ODAME-MENSAH, S. Sandwich Model of Educational Upgrading in Ghana: A Transitional Challenge in Disguise. European Scientific Journal, ESJ, v. 17, n. 8, p. 136, 31 Mar. 2021.