Material from other institutions Notes and curricula, Maria Grey College, 1930-1931; examination papers from the National Froebel Union and the University of Reading, 1934-1939; leaflets concerning evening classes taught by NH for the Froebel Society and Junior Schools Association, 1930s; prospectuses and leaflets from the Warburg Institute, Hampstead Garden Suburb and the Harvard Research Centre in Creative Altruism 1930s-1960s