Wine subject to a specific ageing period in wood or in bottle. In order to be classified as a reserva tinto, wine must spend at least 36 months in a cask or bottle, of which at least 12 months should be in oak casks. For blanco and rosado wines the ageing period is 24 months minimum, with at least six months spent in oak casks. Found on http://www.decanterwines.co.uk/page/spanishWineGlossary/
(Spain) In Spain, red wines designated as reserva have received a minimum of three years ageing prior to release, of which at least one must be in oak. Related terms include Gran Reserva and Crianza. Found on http://www.encyclo.co.uk/local/21497
Sp. Spanish law requires Reserva red wines to be aged a minimum of 3 years, at least 1 of which must be in oak. Whites and roses must be aged a minimum of 2 years with at least 6 months in oak. Found on http://www.supplewine.com/wine101/glossary/