1. Tinctura guajaci und ein ozontrager, als reagens auf sehr geringe Blutmengen, nämentlich in medico-forensischen fallen;VanDeen;Arch. f. d. Holland. Beitr Naturkd Heilk,1861
2. The influence of iron on the benzidine and guaiac tests for occult blood;Burger;Guy Hosp Rev,1934
3. Occult blood in the feces and its clinical significance;Steele;Medical Chronicle,1905
4. The detection of occult blood in feces including observations on the ingestion of iron and whole blood;Peranio;J Lab Clin Med,1951
5. Significance of guaiac and orthotolidine tests after ingestion of iron;Morgan;JAMA,1957