June 17, 1984
Dear Dr. Varmus,
I was pleased to receive your letter of May 11, 1984 and thank you for your interest.  We would indeed be interested in a collaboration with you. Currently, we are involved in attempting to characterize the virus and to determine its relation to the other lentivirus group.
I would very much like to hear your ideas on the framework for our collaboration.
As I will be leaving the lab for a period of approximately two months, I hope that we may be able to initiate the collaborative study upon my return sometime toward the end of September, early October.
Sincerely yours,
Professor Kalman Perk