REMOVE

1. Portrait photographs
2. Photographs
3. Acetate negatives
4. Photographers.
5. Library of Congress Prints a …
6. 1942

WHAT

1. Acetate negatives (1)
2. Portrait photographs (1)
3. negative (1)

WHO

1. Library of Congress Print … (1)
2. Unknown (1)

WHEN

1. 1911 (1)
2. between 1911 and 1942 (1)