Year 23 BC was either a common year starting on Saturday or Sunday or a leap year starting on Friday , Saturday or Sunday ( link will display the full calendar ) of the Julian calendar ( the sources differ , see leap year error for further information ) and a common year starting on Friday of the Proleptic Julian calendar .
Year 23 BC was either a common year starting on Saturday or Sunday or a leap year starting on Friday , Saturday or Sunday of the Julian calendar .