Jungfrau-Aletsch: Wandern am Rande des Welterbes
Author(s): Peter Anliker
Publisher, year: Conrad Stein Verlag, 2011

Available in German at Amazon.co.uk, Amazon.fr and Amazon.de.

Schweiz: Walserweg
Author(s): Hans Hönl
Publisher, year: Conrad Stein Verlag, 2011

Available in German at Amazon.co.uk, Amazon.fr and Amazon.de.

Ossola-Täler - die schönsten Tal- und Höhenwanderungen
Author(s): Hans Schmid
Publisher, year: Bergverlag Rother, 2001. A 3rd edition has appeared in 2012

Available in German at Amazon.co.uk, Amazon.com, Amazon.fr and Amazon.de.

Entdeckertouren Oberwallis
Author(s): Eugen E. Hüsler
Publisher, year: Bruckmann, 2010

Available in German at Amazon.co.uk, Amazon.fr and Amazon.de.

Wandern in den Vispertälern
Author(s): Christoph Käsermann
Publisher, year: Ott Verlag, 2008

Available in German at Amazon.de.

Gletscher der Schweiz: 52 faszinierende Bergwanderungen zu Eisströmen in den Kantonen Bern, Wallis und Waadt
Author(s): Christoph Käsermann, Andreas Wipf
Publisher, year: Ott Verlag, 2011

Available in German at Amazon.de.

Magisches Tessin: Wanderungen zu Orten der Kraft
Author(s): Elmar Good
Publisher, year: AT Verlag, 2007

Available in German at Amazon.co.uk, Amazon.fr and Amazon.de.

Au pays des bisses et inventaire des bisses valaisans
Author(s): -
Publisher, year: Editions Ketty & Alexandre, 2000

Les Neiges et Rocs du Randonneur: itinéraires d'altitude dans les Alpes vaudoises et valaisannes
Author(s): F. Weill
Publisher, year: Cêtre, 2008

Available at Amazon.fr.

Finally! Here is the long awaited reprint of what I consider to be the best guide of this long list! Needless to add that it's worth buying it. Most of the itineraries have been kept in this new version, with a revised route description if the changing conditions made it necessary. A handful of new routes have been added. Pity that it seems so little known! At least this time it is apparently easier to get a copy.