1. Spectroscopic and chemical demonstrations of occult blood in the feces;Aaron, C.D.;J. Amer. med. Ass,1924
2. Ueber den Nachweis von okkultem Blut in den Faces;Adler, E.;Arch. Verdau. Kr,1921
3. Gastrointestinal haemorrhage and salicylates;Alvarez, A.S.; Summerskill, W.H.J.;Lancet,1958
4. The Gregersen test;Alvarez, R.S.; Wight, T.H.T.;Veterans Adm. med. Bull,1929
5. The guaiac test-correlation with clinical findings;Barnett, R.N.;Gastroenterology,1952