@Misc{Wiki,
 howpublished = {\url{http://en.wikipedia.org/wiki/Vipera_aspis}}
} 

@Book{Kooy2010,
 author = {Kooijman, S.A.L.M.},
 year = {2010},
 title  = {Dynamic Energy Budget theory for metabolic organisation},
 publisher = {Cambridge Univ. Press, Cambridge},
 pages = {Table 4.2 (page 150), 8.1 (page 300)},
 howpublished = {\url{../../../bib/Kooy2010.html}}
} 

@Article{Naul1973,
 doi = {10.1111/j.1748-1090.1973.tb02115.x},
 author = {Naulleau, G.},
 year = {1973},
 title = {Rearing the Asp viper \emph{Vipera aspis} in captivity},
 journal = {International Zoo Yearbook},
 volume = {13(1)},
 pages = {108–111}
}