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Keywords from Image Description:
Sommer Giorgio n. Gotthardbahn Sisikon cropped. Giorgio Sommer Gotthardbahn Traforo del San Gottardo Sisikon Numero di catalogo Giorgio Sommer Gotthardbahn Sisikon Catalogue Sommer Giorgio GotthardbahnSisikon before retouched image Sommer Giorgio GotthardbahnSisikon Creator Giorgio Sommer derivative work Gestumblindi