A personal website of mine had received a few really good one-way links from government websites, but only for a short period of time--kind of like seasonal references and when the season was over the links were removed.
The links were so good that rankings for pages the links pointed to went from no where to first page within a couple of days.
Thing is, the links have been removed but the pages still rank super well, not quite as well as before but still darn well.
Makes me think that Google remembers links and gives ongoing credit for them.