Letter from Carvel Flood, Secretary to Thomas Gold to Dr Leonard Efron and Dr Carlton B Solloway, Jet Propulsion Laboratory, Oak Grove Drive, Pasadena, California Refers to their letter of 3 January inviting Professor Gold to a conference on Scientific Applications of Radio and Radar Tracking in the Space Program on 9-11 April. Professor Gold regrets that he will be unable to attend despite previously sending a form to says that he could and also sending an abstract. Professor Gold now has an important meeting in Washington. Asks if Professor Gold's name can be removed from the list of participants. 6 March 1969