. . . . . . . "Pieter Roeter" . . "P. R." . "H.P.R" . "H.P.R. Frederikse"@en . "Hans Pieter Roeter Frederikse"@pl-PL . "H." . "H. P. R. Frederikse"@fr-FR . "Pieter Roetert" . "Frederikse"@fr-FR . . "1920" . "Hans Pieter Roetert Frederikse"@de-DE . . "Frederikse" . "Hans" . "H. P. R. Frederikse" . . "H.P.R Frederikse" .