The Bibliothèque nationale de France has reissued the old (1956) and only (?) engraving of Schmitt's string quartet op. 112 by Quatuor Champeil. It's available for download here : http://www.qobuz.com/fr-fr/album/schmitt-quatuor-a-cordes-op-112-mono-version-quatuor-champeil/3610156142522?qref=dac_2 (http://www.qobuz.com/fr-fr/album/schmitt-quatuor-a-cordes-op-112-mono-version-quatuor-champeil/3610156142522?qref=dac_2)