An asymmetric characterization of the congruence frame (Q536047)

From the abstract: ``The functor from regular biframes to frames, taking first parts, is shown to be faithful.'' Then the notion of regular biframe extension of frames is introduced, and it is proved that the congruence frame of a frame \(L\), viewed as a biframe (the Skula biframe), is the unique regular biframe extension of \(L\). ``This provides a pointfree analogue to a result of Salbany stating that the forgetful functor from completely regular bitopological spaces to topological spaces, taking first parts, has a unique section.''