V O L . 7 , D O C . 3 9 a P R O P A G A T I O N O F S O U N D 3 7
PD (NL-LeU, Collectie Bibliotheca Publica Latina 3545, Albert Einstein Manuscripts). [123 454].
The last two pages of corrected page proofs of Einstein 1920c (Vol. 7, Doc. 39).
Einstein replaced the crossed-out text with a corrected version, included in Einstein 1920c (Vol. 7,
Doc. 39), and extant in manuscript as [123 455]. See also Velsen 2005 for an analysis of Einstein’s
The paper was published on 29 April 1920.
The corrected equation (18) appears in the published version of Einstein 1920c (Vol. 7, Doc. 39).