@inproceedings{dou_comparing_2014, title = {Comparing {Multi}-constellation and {Multi}-frequency based on {GPS}/ {BeiDou} {RTK} {Positioning}}, booktitle = {{ION} {GNSS}+ 2014}, author = {Dou, Jingjing and O'Keefe, K}, year = {2014}, note = {CP49}, pages = {2317 -- 2325} }