In spite of a small error in a chemical formula, the U.S. Postal Service is going ahead with a commemorative stamp honoring biochemist Gerty Cori. She discovered cori ester, a derivative of glucose.

The formula for the chemical is shown on the stamp. The error is in the placement of a line in the formula and does not create a new chemical, Postal Service spokesman Roy Betts said Tuesday.

The Cori stamp is among a set of four 41-cent stamps honoring American scientists and scheduled to be issued March 6.

The error was discovered by Chemical & Engineering News.