The graph of body size versus metabolic rate by Max Kleiber
<b>Vectorization: </b> <a href="//commons.wikimedia.org/wiki/User:Jeromi_Mikhael" title="User:Jeromi Mikhael">Jeromi Mikhael</a>
Kleiber M. (1947). Body size and metabolic rate. Physiological Reviews 27: 511-541.