No known restrictions on publication. It is the user's obligation to determine and satisfy copyright or other use restrictions when publishing or otherwise distributing materials found in the Library of Congress Prints & Photographs Division's collections.
Source:
PAN SUBJECT - Groups no. 229 (E size) [P&P], Prints and Photographs Division, Library of Congress, Washington D.C. https://www.loc.gov/pictures/resource/cph.3c31957/