Jordán LLuch, Cristina, and Juan Ramón Torregrosa Sánchez. “A Characterization of the Duals of Some Echelon Köthe Spaces of Banach Valued Functions”. Collectanea Mathematica, vol. 38, no. 3, Mar. 2007, pp. 229-48, https://raco.cat/index.php/CollectaneaMathematica/article/view/56956.