Lovell described it is an "Urtext of late Soviet civilization". Other kinds of editions distinct from urtext are facsimile and interpretive editions, discussed below. A fundamental problem in urtext editing is how to present variant readings. Claus Westermann claims that the text of Genesis 6 is based on an Ugaritic urtext. In the extended urtext, 120 bars of music were re-integrated. Via at the piano, was released by the Mexican label Urtext Digital Classics. Urtext editions are also easier to read than facsimiles. The other publication of the same year is by Martino Tirimo (Wiener Urtext). It is thus impossible to produce an "Urtext" (original version) from surviving witnesses. For the recording, Kirill Gerstein was granted special pre-publication access to the new urtext edition. In collaboration with Schott, they have published the Wiener Urtext Edition series since 1972. Prieto has recorded for the Urtext Records, Sony Classical, Naxos, and Avanticlassic labels. Both Paul Badura-Skoda (Henle) and Martino Tirimo (Wiener Urtext) published an Urtext edition in 1997. He is currently editing a new Urtext edition of Beethoven's piano sonatas. The catalogue now comprises around 1500 Urtext editions and around 750 scholarly publications.