The virtual exhibition Primera Guerra Mundial is a project of the Casa de la Imaginem, an audiovisual archive in Logroño, Spain. At their website the Casa shows some thirty photographs taken by an unidentified French officer during the First World War near Ypres, elsewhere in Flanders, at Arras and at the Somme. They form part of a collection with some 500 stereoscopic photographs discovered in 1999 in Tanger. Alas the virtual exhibition shows of each stereoscopic set just one image, but luckily you can view a four minutes video with some of these images at Vimeo. In 2007 an exhibition was held to show these images after restoration; you can download a dossier about it in French or Spanish.
At the French centenary portal Mission Centenaire you can view thirty photographs from the collection at Logroño with full information about the locations shown, again without animated stereoscopic images. There is a link to a fourteen-minute video at Vimeo showing a selection of images, accompanied by music.