Andersen, P. B. & Qvortrup, L. (2004). Introduction. I P. B. Andersen & L. Qvortrup (red.), Virtual Applications.: Applications with Virtual Inhabited 3d Worlds. (s. 1-5). Springer.
Blok, R. (2004). I try to recall... I M. P. Huang, K.-K. Simonsen & M. R. Thomsen (red.), Reinventions of the Novel: History and Aesthetics of a Protean Genre (1 udg., Bind 1, s. 301-320). Brill | Rodopi.
Kullberg, E. (2004). Jan Maegaard. I Musik in Geschichte und Gegenwart, Personenteil bd. 11 Bärenreiter.
Stougaard-Nielsen, J. (2004). Johannes Jørgensen. I M. Stecher-Hansen (red.), Danish Writers from the Reformation to Decadence, 1550-1900.: Dictionary of Literary Biography. (Bind 300, s. 283-293). Gale.