Archaeologists in Guatemala say they've found another reference to the end date on the Mayan calendar.

The newly uncovered 1,300-year-old panels are the second-known reference to the end of the Mayan calendar.

The Mayan calendar begins before 3000 B.C. and runs in roughly 394-year periods called baktuns.

The Mayans held the number 13 sacred and the 13th baktun ends on Dec. 21, 2012.

A Mayan scholar and professor of Mesoamerican art from the University of Texas at Austin described his amazement at the discovery.

"I was very amazed and amused yesterday to notice that that panel records the date of the end of the 13th baktun (20 cycles of the Mayan long count calendar), which for us is coming up in just a few months time in December of 2012," Dr. David Stuart said. "Here we have a Mayan monument that was carved 1,500 years ago that's talking about the year we're in right now."