Cuerno, Rodolfo2010-03-082010-03-081991-11-21Physics Letters B, 1991, vol. 271, n. 3-4, p. 314-3200370-2693https://hdl.handle.net/10016/71617 pages, no figures.-- MSC2000 codes: Primary: 81R50; Secondary: 17B37, 17B81, 81R10.MR#: MR1140143 (92m:81106)$W_n$ algebras are considered in their free field representation to show that they are endowed with a quantum group symmetry which is a $Z_2$ twist à la Drinfel'd of $U_{q+}({\rm sl}(n))\times U_{q-}({\rm sl}(n))$. We use the contour picture of quantum groups due to Gómez and Sierra. A sample computation for the $R$ matrix is also performed.application/pdfeng© Elsevier[MSC] Quantum groups and related algebraic methods[MSC] Quantum groups (quantized enveloping algebras) and related deformations[MSC] Lie algebras and Lie superalgebras For Lie groups: Applications to physics[MSC] Infinite-dimensional groups and algebras motivated by physics, including Virasoro, Kac-Moody, W-algebras and other current algebras and their representationsresearch articleMatemáticashttps://www.doi.org/10.1016/0370-2693(91)90093-6open access