# How is the complexity of PCA $O(\min(p^3,n^3))$?

I've been reading a paper on Sparse PCA, which is: http://stats.stanford.edu/~imj/WEBLIST/AsYetUnpub/sparse.pdf

And it states that, if you have $n$ data points, each represented with $p$ features, then, the complexity of PCA is $O(\min(p^3,n^3))$.