What is the complexity of gspan algorithm?

algorithm and subprocedure I have inspected gpan algorithm of the article "gspan: Graph-based Structure Pattern Mining".

The link of the article is http://ift.tt/2jYyrHm

Now, I want to find the complexity of the Algorithm 1 that can be seen in the attached image.

I think the subprocedure calls itself in a recursive manner, and it is like a DFS.

How can I find the total complexity of Algorithm 1 in big-O notation that calls the subprocedure inside it?