RT Journal Article SR Electronic T1 Dark-Ground Illumination of Unstained Smears and Tissue Sections for the Diagnosis of Treponema Pallidum JF The British Journal of Venereal Diseases JO Br J Vener Dis FD BMJ Publishing Group Ltd SP 97 OP 99 DO 10.1136/sti.28.2.97 VO 28 IS 2 A1 Coutts, Waldemar E. A1 Silva-Inzunza, Edna A1 Morales-Silva, Guillermo YR 1952 UL http://sti.bmj.com/content/28/2/97.abstract AB