Presas i Puig, A. (2005). Spain in 1952 as seen by a German warship builder: Modernisation programmes of the submarine fleet under Franco's first regime and German specialists. Max-Planck-Institut für Wissenschaftsgeschichte.

Presas i Puig, Albert. Spain in 1952 as Seen by a German Warship Builder: Modernisation Programmes of the Submarine Fleet Under Franco's First Regime and German Specialists. Berlin: Max-Planck-Institut für Wissenschaftsgeschichte, 2005.

Presas i Puig, Albert. Spain in 1952 as Seen by a German Warship Builder: Modernisation Programmes of the Submarine Fleet Under Franco's First Regime and German Specialists. Max-Planck-Institut für Wissenschaftsgeschichte, 2005.