Morten Tønnessen
(2019). What can be known about future Umwelten?. The American Journal of Semiotics 35 (3-4), pp. 401-429.
(2015)., Umwelt and language, in E. Velmezova, K. Kull & S. J. Cowley (eds.), Biosemiotic perspectives on language and linguistics, Dordrecht, Springer, pp. 77-96.
(2014). The ontogeny of the embryonic, foetal and infant human umwelt. Sign systems studies 42 (2-3), pp. 281-307.
(2011)., Semiotics of being and Uexküllian phenomenology, in A. Tymieniecka (ed.), Phenomenology/ontopoiesis retrieving geo-cosmic horizons of antiquity, Dordrecht, Springer, pp. 327-340.
(2009). Abstraction, cruelty and other aspects of animal play (exemplified by the playfulness of Muki and Maluca). Sign systems studies 37 (3-4), pp. 558-578.
(2009). Umwelt transitions: Uexküll and environmental change. Biosemiotics 2 (1), pp. 47-64.
(2003). Umwelt ethics. Sign systems studies 31 (1), pp. 281-299.