Cloning and physical mapping of RNA polymerase genes from Methanobacterium thermoautotrophicum and comparison of homologies and gene orders with those of RNA polymerase genes from other methanogenic archaebacteria.
Schallenberg J, Moes M, Truss M, Reiser W, Thomm M, Stetter KO, Klein A. J Bacteriol. 1988 May; 170(5):2247-53.