Monthly Notices of the Royal Astronomical Society
Long-term light curves of the cataclysmic variable BK Lyn = PG 0917 + 342 from the Indiana Automated CCD photometric telescope (‘RoboScope’) and the Harvard College Observatory plate archive reveal no dwarf nova outbursts. Two radial velocity studies show its orbital period to be 107.97 ;1 0.07 min, confirming that it does have an orbital period shorter than the period gap for cataclysmic variables. Whether this is the first nova-like variable below the period gap or a dwarf nova with rare outbursts resembling WZ Sge is still unclear, however.
Ringwald, F. A.; Thorstensen, J. R.; Honeycutt, R. K.; and Robertson, J. W., "The Orbital Period of BK Lyncis (PG 0917 + 342)" (1996). Open Dartmouth: Faculty Open Access Articles. 1878.