TURGEON, Alfred; DIBIASE, David; MILLER, Gary. Introducing the Penn State World Campus through Certificate Programs in Turfgrass Management and Geographic Information Systems. Online Learning, Boston, MA, v. 4, n. 3, 2019. DOI: 10.24059/olj.v4i3.1898. Disponível em: https://olj.onlinelearningconsortium.org/index.php/olj/article/view/1898. Acesso em: 25 mar. 2026.