Analysis of information sources in references of the Wikipedia article "Ley del valor" in Spanish language version.
Cita: Labour, like all other things which are purchased and sold, and which may be increased or diminished in quantity, has its natural and its market price. The natural price of labour is that price which is necessary to enable the labourers, one with another, to subsist and to perpetuate their race, without either increase or diminution. Traducción al español: La labor, como todas aquellas cosas compradas y vendidas, y el cual puede incrementar o disminuir en cantidad, tiene su precio natural y su precio de mercado. El precio natural de la labor es aquel precio necesario para habilitar a los trabajadores, uno con otro, a subsistir y perpetuar su raza, sin aumento ni disminución.