S1 문장의 [______]에 들어갈 단어는?

난이도 필수 · 힌트를 덜 열수록 높은 점수 (현재 5점)
Even though the first successful appendectomy was said to have been performed by a British army surgeon in 1735, it wasn't until the 1880s that the procedure was described in medical [______] and taught in medical schools.