found: His Outline of a grammar of the Turkish language, 1856:t.p. (Elias Riggs)
found: Andover Theological Seminary. General catalogue, 1909(Elias Riggs; grad. 1832; missionary to Greece and Turkey; translator of Bible and hymn books; author of textbooks; instructor of Hebrew and Chaldee at Union Seminary; b. New Providence, N.J., 11/19/1810; d. 1/17/1901 at Constantinople)
found: Genov, G., Amerikanskii︠a︡t prinos za vŭzrazhdaneto na bŭlgarshtinata, s osoben ogled kŭm lichnostta na Ilaĭŭs Rigs, 2008:t.p. (Илайъс Ригс = Ilaĭŭs Rigs [rom.]; Elias Riggs)