Oohh interesting. From the Wikipedia article on February, 1923:
February 28, 1923 (Wednesday)
The nation of Greece used the Julian calendar for the last time before adopting the Gregorian calendar, used by most of the world, the next day. In that the Julian calendar was 13 days behind the Gregorian, the day was noted as "February 15". The next day was March 1 rather than February 16.
February 28, 1923 (Wednesday)
The nation of Greece used the Julian calendar for the last time before adopting the Gregorian calendar, used by most of the world, the next day. In that the Julian calendar was 13 days behind the Gregorian, the day was noted as "February 15". The next day was March 1 rather than February 16.