Focal infection theory's modern era really began with physician Frank Billings, based in Chicago, and his case reports of tonsillectomies and tooth extractions claimed to have cured infections of distant organs. Replacing Hunter's term "oral sepsis" with "focal infection", Billings in November 1911 lectured at the Chicago Medical Society, and published it in 1912 as an article for the American medical community. In 1916, Billings lectured in California at Stanford University Medical School, this time printed in book format. Billings thus popularized intervention by tonsillectomy and tooth extraction. A pupil of Billings, Edward Rosenow held that extraction alone was often insufficient, and urged teamwork by dentistry and medicine. Rosenow developed the principle "elective localization", whereby microorganisms have affinities for particular organs, and also espoused extreme pleomorphism.