fixed z -> phi as pointed out by nameEqualsJared

commonCoordinates/digInSphericalCoordinates.tex

@@ -97,7 +97,7 @@ \section{Triple integrals in spherical coordinates}
 \int_a^b\int_c^d\int_p^q F(x,y,z) \d y \d x\d z
 \]
 Now consider representing a region $R$ in spherical coordinates and
-let's express $\d V$ in terms of $\d \rho$, $\d\theta$, and $\d z$. To
+let's express $\d V$ in terms of $\d \rho$, $\d\phi$, and $\d \theta$. To
 do this, consider the diagram below:
   \begin{image}
     \begin{tikzpicture}