I herewith warmly recoamaend for participation in the Harvard
Summer Seminar iir J. £iebenga whom I know as a student at the
Netherlands School of Economics at Rotterdam,
^ Piebenga was a very active and capable student and his contributions to my seminar were excellent. He combined a thorough
Ins^t in economic questions with a very good understanding of social and human matters.
(J, Tinbergen)
Professor of Econometrics
at the
Rotterdam School of Economics
