  The Polyakov linear sigma model (PLSM) is used to investigate the respective
influence of a finite volume and a magnetic field on the quark-hadron phase
boundary in the plane of baryon chemical potential ($\mu_{B}$) vs. temperature
($T$) of the QCD phase diagram. The calculated results indicate sizable shifts
of the quark-hadron phase boundary to lower values of $(\mu_{B}~\text{and}~T)$
for increasing magnetic field strength, and an opposite shift to higher values
of $(\mu_{B}~\text{and}~T)$ for decreasing system volume. Such shifts could
have important implications for extraction of the thermodynamic properties of
the QCD phase diagram from heavy ion data.
