Leading later efforts to establish the identity of Greve/Grove by unearthing new biographical information and relevant records, Klaus Martens has been "the chief pioneer" (W.J. Keith). Exploring both the European and Canadian contexts, Martens published "Felix Paul Greves Karriere" (in German), "Felix Paul Greve – André Gide" (correspondence in English, French, and German), and "F. P. Grove in Europe and Canada: Translated Lives", the first well documented biography of the author in English. Martens' vast compilation "Over Canadian Trails: F.P. Grove in New Letters and Documents" includes the most extensive published collection of letters from and to Grove, including the Phelps correspondence, documents, many photographs, and much relevant commentary by the editor. This was preceded by Martens' "A Dirge for My Daughter", a careful edition of selected poems by Grove which includes photographs and reproductions of handwritten letters and notes. In addition to his Grove monographs and editions, Martens published numerous articles on both Grove and Else Plötz.