role in the uncertainties of the derived IMFs, especially since stellar age, stellar metallicity, galactic dust, galactic SFH, and stellar IMF cannot be easily disentangled [@Conroy2013]. Furthermore, indirect IMF results may depend strongly on more sophisticated features of stellar population models \[mainly stellar rotation, binary evolution of O and B stars and the treatment of Wolf–Rayet (W-R) stars [@Wolf2000]\] and dark matter profiles of galaxies. @Smith2014 showed that galaxy by galaxy comparisons of inferred IMF mass factors via dynamical and spectroscopic fitting techniques can lead to inconsistent results due to our limited understanding of element abundance ratios, dark matter contributions, and/or more sophisticated shape of the IMFs [@McDermid2014; @Smith2014].

The concept of an IMF was first introduced by @Salpeter1955 as a logarithmic slope $\Gamma$ defined by, $$\label{eq:imf_def_salp}
\Phi(\log\ m)=dN/d(\log\ m) \propto m^{\Gamma}$$ where $m$ is the mass of a star, $N$ the number of stars within a logarithmic mass bin, and $\Gamma=-1.35$ is the slope of the IMF. Historic studies of the IMF slope at the high mass end (M $\gtrsim$ 1 [M$_\odot$]{}) showed no statistically significant differences from the value derived by Salpeter giving rise to the concept of IMF universality [@Scalo1986; @Gilmore2001]. Theoretical studies attempt to explain the 