Letter from Carrie Gold to Mr Yung S Liu, Optical society of America, General Electric R & D Center, Bldg K-1, Rm. 4B26, PO Box 8, Schenectady, New York Apologises for the delay in replying tohis letter, as they have just come back from vacation, Has been asked to say that Professor Gold very much regrets he will not be able to travel to Albany this semester, because the class load is much heavier than expected and it will not be possible to add any more travel to his already too busy schedule. Perhaps some other year would be possible. 30 January 1979