The name, place and date 'Kapp UNESCO, Paris 1947' are written on the front of the sketch. On the back of the photograph is the reference:' K.24'.

There is a short letter from Kapp to Joseph Needham dated 22 April 1948 in the Cambridge University Library Joseph Needham UNESCO papers (Section D), saying that he is sending the drawing of Huxley, and he can provide Joseph Needham with more copies of the Joseph Needham sketch if need be.