TY - JOUR AU - Hertrich-Jeromin, Udo TI - Supplement on curved flats in the space of point pairs and isothermic surfaces: A quaternionic calculus JO - Documenta mathematica PY - 1997 SP - 335 EP - 350 VL - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/DOCMA_1997__2__a2/ LA - en ID - DOCMA_1997__2__a2 ER -