Typed letter signed, dated July 24, 1972 by the Romanian mathematician and statistician, professor at Harvard and nominated for the Nobel Prize in Economics. Georgescu-Roegen addresses a colleague thanking him for the article he has been sent: “…The one on the relation between entropy and association interested me in a special way (because of my own interest in the general basis of the entropy concept…”. 1 p. with “Vanderbilt University” letterhead. In fine condition. Envelope with autograph address included Included: Greeting card with autograph lines and signature.