context: When Bjerknes' grant ended, he was hired by Otto Pettersson as his main assistant at the Swedish Hydrographic and Biological Commission.
source: Pettersson is the chief scientist of the Commission's research vessel fleet.
reference_original: Pattersson es el científico principal de la flota de navíos de investigación de la Comisión.
reference_flipped: Pattersson es la científica principal de la flota de navíos de investigación de la Comisión.