Mappes, T. (2012). "The Invention of Immersion Ultramicroscopy in 1912—The Birth of Nanotechnology?". Angewandte Chemie International Edition. 51 (45): 11208–11212. doi:10.1002/anie.201204688. PMID23065955.
Mappes, T. (2012). "The Invention of Immersion Ultramicroscopy in 1912—The Birth of Nanotechnology?". Angewandte Chemie International Edition. 51 (45): 11208–11212. doi:10.1002/anie.201204688. PMID23065955.