Scanned Endgame Study Books

Joseph Kling, Bernard Horwitz: Chess studies; or endings of games 1851
Kubbel_150_endspielstudien_1925.djvu
Platov_Sbornik sachmatnych etjudov_1928.djvu
Herbstmann_Sovremennyj sachmatnyj etjud_1937.djvu
Prokes_Šachové studie - 150 miniatur_1941.pdf
Prokop_212 šachových studií_1944.pdf
Prokes_Kniha šachových studií_1951.pdf
Fritz_Moderní šachová studie_1951.pdf
Fritz_Šachová studie_1954.pdf
Gulyaev_Izbrannye sachmatnye zadachi i etjudy_1956.djvu
Korolkov_Izbrannye_etjudy_1958.djvu
Chekhover_Shakhmatnie etiudy i okonchania_1959.djvu
Gurvitch_Etjudy_1961.djvu
Herbstmann_Izbrannye_etudy_1964.djvu
Troitzky_360_endgames_1968.pdf
Bondarenko_Etyud v peshechnom okonchanyi_1973.djvu
Bondarenko_Stanovlenie_sachmatnogo_etjuda_1980.djvu
Kasparjan_Domination_in_2545_endgame_studies.djvu
Bondarenko_Razvitie_sachmatnogo_etjuda_1982.djvu
Umnov_Putjami sachmatnovo tvorcestva_1983.djvu
Bondarenko_Triumf_sovetskogo_etjuda_1984.djvu

Books on endgame theory:
averbach1_1980.djvu
averbach2_1981.djvu
averbach3_1982.djvu
averbach4_1983.djvu
averbach5_1984.djvu

You can find further links to chess composition books on the following site:
http://web.iol.cz/vaclav.kotesovec/