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

@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}}
} 

@Misc{fishbase,
 howpublished = {\url{https://www.fishbase.se/summary/Potamotrygon-motoro}}
} 

@article{ChaoLiu2014,
 author = {Liu Chao and Liu, Yi and Lai, Ming-xin and Qiu, Bao-jun and Luo, Jian-ren and Hu, Yin-chang},
 title = { Artificial propagation and growth characteristics of \emph{Potamotrygon motoro}},
 year = {2014},
 journal = {Guangdong Agricultural Sciences},
 volume = {9},
 pages = {135}
}