The volume below the function $z=f(x,y)$ and above the region $R$ is given by $V=\iint_{R} f(x,y) \, dA$. In this case, $f(x,y)=x^{2}+3y^{2}$ and the region $R$ is bounded by $y=x^{2}$ and $y=x$. So, the volume can be written as:
\[V=\iint_{R} (x^{2}+3y^{2}) \,
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