'Reference & loose oddments.' Comprises chiefly a typescript report by Helen Megaw on C Willaime & W L Brown, 'A Coherent Elastic Model for the Determination of the Orientation of Exsolution Boundaries: Application to the Feldspars', and related correspondence with Henry Lipson, British Co-Editor of Acta Crystallographica, 1973. Also contains 2 letters to Helen Megaw from Peter Gay, Cambridge Dept of Mineralogy and Petrology, discussing an oscillation photograph (enclosed), 1956.