sentences:  He also visited the physics laboratories of the universities of Geneva and Heidelberg, and the International Bureau of Weights and Measures in Paris.On returning to Spain, Cabrera used the techniques he had learned during his European tour, especially those developed in the Zurich laboratory, to continue his research on magnetism, in collaboration with other researchers such as Enrique Moles Ormella and Arturo Duperier.Cabrera's research work was prolific.