Schlegel, R., ‘Encyclopedic Dictionary of Plant Breeding’, (ISBN: 1-56022-950-0), Haworth Press, New York, London, Oxford, USA, 2003, pp 563

Schlegel, R., ‘Rye (Secale cereale L.) – a younger crop plant with bright future’, eds. R. J. Sing and P. Jauhar, in: Genetic Resources, Chromosome Engineering, and Crop Improvement: Vol. II Cereals (ISBN: 0849314305),  CRC Press, Boca Raton, USA, 2006, pp 365-394

Schlegel, R., ‘Concise Encyclopedia of Crop Improvement : Institutions, Persons, Theories, Methods, and Histories’, ISBN: 978-1-56022-146-3, Haworth Press, New York, London, Oxford, USA, 2007, pp 331

Schlegel, R., ‘Dictionary of Plant Breeding’, 2nd ed. , (ISBN-13: 9781439802427), Taylor & Francis, Inc., USA, 2009, pp 584

Schlegel, R., ‘Spermien mögen Maiglöckchen – Kurioses aus Botanik, Züchtung und Genetik’, ISBN: 978-3-83915-284-3, BoD GmbH Verlag, Norderstedt, http://www.bod.de, Deutschland, 2010, pp 368