2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/215346This is a survey of results on surfaces in noncommutative three-dimensional Lie groups obtained by using the Weierstrass (spinor) representation of surfaces. It is based on the talk given at the conference "Geometry related to the theory of integrable systems" (RIMS, Kyoto, September 2007).18 pagesDifferential Geometrytext