Gerd Fraenkel & interlinguistics

Gerd Fraenkel is a figure in the history of interlinguistics. Note the Gerd Frankel Papers at Vanderbilt University. Here are some documents online in which Fraenkel plays a role:

Broadribb, Donald. "Esperanto and the ideology of constructed languages," International Language Reporter, 2nd Quarter 1970, pp. 1-9.

Culbert, Sidney I. Letter to Mr. Albert C. Aumuller, The World Almanac, April 25, 1967. See also Esperanto translation.

Krueger, J. R. "Nabokov's Zemblan: A Constructed Language of Fiction," Linguistics, vol. 5, issue 31, Jan. 1967, pp. 44–49.