Kollwitz, K., & Zigrosser, C. (1969). Prints and drawings of Kathe Kollwitz. Dover Pub.
Lua i Stíl Chicago (17ú heag.)Kollwitz, Kathe, agus Carl Zigrosser. Prints and Drawings of Kathe Kollwitz. New York: Dover Pub, 1969.
Lua MLA (9ú heag.)Kollwitz, Kathe, agus Carl Zigrosser. Prints and Drawings of Kathe Kollwitz. Dover Pub, 1969.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.