H.119-H.121: Heatley, N.G. Heatley was a member of the team of scientists under H.W. Florey who produced in Oxford and tested and investigated penicillin. He also contributed to some of the early work on cephalosporium cultures. Includes 'The antibiotic from tulip', a typescript and manuscript draft with manuscript comments by Abraham, and papers regarding the history of penicillin. 1948, 1962, 1983-1991.

H.122: Hopwood, D.A. Hopwood was the head of the Department of Genetics, John Innes Institute, Norwich. Correspondence regarding research. 1982.

H.123-H.125A: Huddleston, J.A. (née Mitchell). Huddleston worked as a research assistant in Abraham's laboratory from October 1974. Correspondence regarding appointment, research notes, and drafts. 1974-1980.

H.126-H.131: Jayatilake, G. S. Jayatilake was a Sri Lankan organic chemist who came to Abraham's laboratory in 1978 where he worked on the biosynthesis of penicillins and cephalosporins in cell-free systems. Correspondence and papers regarding career and appointments, research reports, and printed material. Principally references and recommendations. 1978-1993.