He became most notable for his two-volume work Flora of Cyprus (1977 and 1985), the first comprehensive contribution about the almost 1750 plant taxa from Cyprus. Other works including parts of the encyclopedia Flora Europaea, Willows and Poplars of Great Britain and Ireland from 1984 and Garden Plants from 1963. He has written articles for the Irish Naturalists' Journal since the 1940s and he was editor of the Draft index of author abbreviations compiled at the Herbarium, Royal Botanic Gardens, Kew from 1980.
