'Invitations to me & replies', including: correspondence with Arthur R von Hippel of MIT concerning the possibility of a 3 month period of work with MIT research groups, 1962; correspondence with the UK Atomic Energy Authority concerning the possibility of the appointment of Helen Megaw as a consultant, 1961; invitation from Physica Status Solidi, Berlin, to contribute to the journal, 1962; request from the Admiralty Signal & Radar Establishment for assistance in the study of ferrite materials, 1958.