I imagine it is like any intersection without traffic control: first to arrive has right-of-way. If two bikes arrive at the same time, you must yield to the person on your right. Anyone turning across a lane must yield to oncoming traffic.
2011 Jamis Quest "Cy"
2009 Trek 7500 "Diesel"
2008 Rans Stratus LE recumbent "The 'Bentley"