Peter Kropotkin Quotes about Struggle
Peter Kropotkin (2012). “Anarchism: A Collection of Revolutionary Writings”, p.113, Courier Corporation
Peter Kropotkin (2012). “Mutual Aid: A Factor of Evolution”, p.247, Courier Corporation
"Mutual Aid as a Factor in Evolution". "The Cry for Justice: An Anthology of the Literature of Social Protest". Book by Upton Sinclair, 1915.