At the moment on the PIONIER DLF website you can search in collections of 58 digital libraries. It is estimated that the number of growth of the number of publications is 15 000 each month. All publications are available without any fee. The list of cooperating digital libraries can be found at http://fbc.pionier.net.pl/owoc/list-libs.
After the first year of operation p_b_c resources are already 1% of all publiactions in Polish digital libraries