One notebook and two files, as follows:
Notebook containing ms draft of 'The high temperature phases of sodium niobate' [1965?];
File containing graphs, tables, notes and correspondence on 'high temperature phases - - - ', 1964-65 (this file also contains later notes on 'displacement of Nb', 1972-73);
File containing graphs, tables, notes, figures etc on 'High temperature phases of NaNbO3 [sodium niobate]', including various summaries 'of Lef's work' [1965].