The Production of Extruded Semifinished Products from Metallic Materials,
Abstract
Aluminum alloys are covered on pages 207 -239 The hot-working process extrusion is covered for a wide selection of metals with varying degrees of extrudability. This is the translation of a German book, so  6061 appears only once. In text AlMgSiCu and AlMg1SiCu are used approximately 10 times for 6061.