I found a couple of articles online, and they just referred to the Town Council's desire for just four times a year, while Calvin preferred every week. But there is a mention, by Godfrey of Westminster West, that Calvin did not think it a big deal, and the Council seemed to think that every Lord's Day was too much.
Other than that, the only reference to the reasons for quarterly observance seems to have been Zwingli's view, which seems a bit arbitrary. I find no reasons for it given. But it seems that most of what I've read ties the quarterly observance to Zwingli. Godfrey calls is a Zwingli influence in the Reformed Churches. But the Genevan Town Council's decision could have been all their own as well, without Zwingli's influence.
The reason I'm interested is that quarterly observance seems to have been one of the few things that remained unchallenged, even to this day, of the practices of the Reformed churches. It is just curious that this has been so, but that a good Biblical basis for it is not given. Nor can I find a good argument for why this tradition is valued.
I'll see if I can find those books. I was hoping to just click my mouse, but it seems I have to click my heels. Thanks brothers.
I did find a nice history on Lord's Supper. It was rather general, but still covered a lot of its history, and as well as giving a lot of sources. Most of the references were to Schaff's history.