"Frontmatter". Band 11 Physikvorlesung, edited by Ernst Grumach and Hellmut Flashar, Berlin, Boston: De Gruyter, 1967, pp. 1-4. https://doi.org/10.1515/9783112612163-fm
"Frontmatter" In Band 11 Physikvorlesung edited by Ernst Grumach and Hellmut Flashar, 1-4. Berlin, Boston: De Gruyter, 1967. https://doi.org/10.1515/9783112612163-fm