H. Valkama, P. Martikainen, and M. Räty, “First record of North American ambrosia beetle <i>Gnathotrichus materiarius</i> (Fitch) (Coleoptera, Scolytidae) in Finland - a new potential forest pest?”, Entomol. Fennica, vol. 8, no. 4, pp. 193–195, Dec. 1997.