“He [Hitler] had learned much from Leon Trotzky, whose slogan of the permanent revolution he now adopted: ‘The German Revolution will not be concluded until the whole of the German nation is given a new form, a new organization, and a new structure.”

Diary entry, shortly after the death of Gustav Mahler (1911). Quoted in Oxford University Press, Grove music online: Strauss, Richard, §7: Instrumental works (written by Bryan Gilliam and Charles Youmans).
Other sources

Speech to the Labour Party Conference in Caxton Hall, London (12 December 1944), quoted in The Times (13 December 1944), p. 2.
War Cabinet

As quoted in Men in Motion, Henry J. Taylor, Doubleday, Doran & Co., New York: NY, (1944) p. 59. Also quoted in As We Go Marching, John T. Flynn, New York: NY, Free Life Edition (1973) p. 154, first published 1944 https://mises-media.s3.amazonaws.com/As%20We%20Go%20Marching_2.pdf
Other remarks

"My War Memories, 1914–1918" - by Erich Ludendorff - 1919

Source: Hitler’s Beneficiaries: Plunder, Racial War, and the Nazi Welfare State (2007), pp. 7-8

Hymn

Source: The Greening of America (1970), Chapter I : The Coming American Revolution, p. 4
Context: There is a revolution coming. It will not be like revolutions of the past. It will originate with the individual and with culture, and it will change the political structure only as its final act. It will not require violence to succeed, and it cannot be successfully resisted by violence. It is now spreading with amazing rapidity, and already our laws, institutions and social structure are changing in consequence. It promises a higher reason, a more human community, and a new and liberated individual. Its ultimate creation will be a new and enduring wholeness and beauty — a renewed relationship of man to himself, to other men, to society, to nature, and to the land.
This is the revolution of the new generation.

Van Paassen interview (1936)
Context: We know what we want. To us it means nothing that there is a Soviet Union somewhere in the world, for the sake of whose peace and tranquility the workers of Germany and China were sacrificed to Fascist barbarians by Stalin. We want revolution here in Spain, right now, not maybe after the next European war. We are giving Hitler and Mussolini far more worry with our revolution than the whole Red Army of Russia. We are setting an example to the German and Italian working class on how to deal with Fascism.

"Good Sports & Bad", p. 335; originally published in The New York Review of Books (1995-03-02)
Triumph and Tragedy in Mudville (2003)