 In the twentieth century, the German scholars Friedrich Gennrich and Hans Spanke developed two distinct theories about the textual and melodic form of the "rotrouenge", implicitly suggesting in the process that some of the few specimens of lyric labelled as such in the manuscripts are in fact mis-labelled and do not represent the "rotrouenge".The French scholar Jean Frappier noted that "we are not absolutely sure that we have any authentic specimens of the rotrouenge", indicating that by the time the term came into use in the late twelfth century it was no more than an archaism ("an attractive old term" in the words of Hendrik van der Werf) and that the original genre may have lost its distinct identity.The following are the only four "retroenchas" that survive