Related Rule
Practice Relating to Rule 117. Accounting for Missing Persons
Section B. Provision of information on missing persons
Spain’s LOAC Manual (2007) states: “Each party to the conflict … must provide all the relevant information on the missing persons to the adverse party.” 
Spain, Orientaciones. El Derecho de los Conflictos Armados, Tomo 1, Publicación OR7–004, (Edición Segunda), Mando de Adiestramiento y Doctrina, Dirección de Doctrina, Orgánica y Materiales, 2 November 2007, § 5.2.d.(6).
Spain’s Law on the Victims of the Civil War and the Dictatorship (2007) states under the heading “Measures to identify and locate victims”:
The public administrations shall draft and offer to all within their jurisdiction maps showing the places where human remains as defined in the previous article [i.e. human remains of persons who disappeared during the Civil War or during the subsequent political repression and whose whereabouts are unknown] are located, including every available piece of complementary information.
The Government shall … elaborate a map of the entire Spanish territory and make it accessible to every interested citizen. The map shall include the data provided by the different administrations. 
Spain, Law on the Victims of the Civil War and the Dictatorship, 2007, Article 12(2).