Pombejra, D. na. “A Traveler in Siam in the Year 1655: Extracts from the Journal of Gijsbert Heeck translated and introduced by Barend Jan Terwiel”. The Journal of the Siam Society, vol. 101, Nov. 2013, pp. 289-91, https://so06.tci-thaijo.org/index.php/pub_jss/article/view/158484.