C.Owers Hansa-Brandenburg Aircraft of WWI Vol.2: Biplane Seaplanes (A Centennial Perspective on Great War Airplanes 18)

The Van Berkel WA

<...>
  The Netherlands Navy requested a two-seat long-range monoplane similar to the Brandenburg W.29. Baumhauer designed a monoplane for Van Berkel that was a completely new design of larger proportions and powered by a Rolls Royce Eagle VIII engine. Six of these WB monoplanes were built and are often referred to as Brandenburgs, but apart from some superficial similarities, the WB was a completely new design. The WB was the last aircraft built by Van Berkel.