Arena, Orazio. “Some Problems on Boundary Controllability for PDEs”. Bullettin of the Gioenia Academy of Natural Sciences of Catania 46, no. 376/SFE (December 31, 2013): SFE12-SFE17. Accessed December 22, 2024. https://bollettino.gioenia.it/index.php/gioenia/article/view/67.