Authier, A.; Klapper, H. (2007). "Gerhard Borrmann (1908–2006) and Gerhard Hildebrandt (1922–2005): their life stories and their contribution to the revival of dynamical theory in the 1950s". Physica Status Solidi A. 204 (8): 2515–2527. Bibcode:2007PSSAR.204.2515A. doi:10.1002/pssa.200675668.
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Authier, A.; Klapper, H. (2007). "Gerhard Borrmann (1908–2006) and Gerhard Hildebrandt (1922–2005): their life stories and their contribution to the revival of dynamical theory in the 1950s". Physica Status Solidi A. 204 (8): 2515–2527. Bibcode:2007PSSAR.204.2515A. doi:10.1002/pssa.200675668.