Sorry, but in "Other designations: PGC 4713558" is incorrect and PGC 4713558 don't exit.  
 Alternative names of Canes Venatixi II dwarf galaxy are: CVn II dSph, SDSS J1257+3419, J1257+3419. (see: http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=SDSS+J1257%2B3419&submit;=SIMBAD+search). 
 Best regards