I do not think that it is any of these writers. Wicksell who comments on
the concept and on previous authors, uses the work "Staffelung" in
inverted commas (Uber Wert, Kapital und Rente, p. 106). Machlup (1958
ZfN) suggests that the term "term structure of production" (in english)
was offered by Hayek in Prices & Production (see FM Economic Semantics 2nd
edn intro by M Perelman, p. 76). I have not consulted Hans Meyer's
article "Produktion" in the Handworterbuch d Staatswissenschaften that
Hayek mentions and praises. Machlup refers to the concept as one the six
tenets of the Austrian School ("Austrian Economics" in Encyclopedia od
Economics 1982)
No cigar, I know.
Nicholas Theocarakis