On a Theorem of Ian Hughes About Division Rings of Fractions

Warren Dicks, Dolors Herbera, Javier Sánchez
2004 Communications in Algebra  
Let G be a locally indicable group, K a division ring, and KG a crossed-product group ring. In 1961, Ian Hughes proved that, up to KG-isomorphism, at most one division ring of fractions of KG satisfies a certain independence condition, now called Hughes freeness.
doi:10.1081/agb-120027970 fatcat:65t7wbzcffcnpkfg42rqp3ycnm