TY - RPRT TI - Letter: Negative complement-fixation tests as an immunopathological finding. AU - K Penttinen AU - O Wager AU - S Pyrhönen AU - P Leinikki AU - A M Teppo PY - 1974 DO - 10.1016/s0140-6736(74)93136-5 UR - https://pubmed.ncbi.nlm.nih.gov/4131227/ ID - 4131227 ER -