The construction of the Willemsspoort tunnel near the Botersloot and the office building of the PTT. (Post, Telegraph and Telephone service). Year: 1989.
Alex (Lex) (A.) de Herder
<a rel="nofollow" class="external text" href="https://hdl.handle.net/21.12133/FEA0D98B62AD4B9885BA65477BB99735">Stadsarchief Rotterdam</a>