United States
usa-20010627-s-001
page = 1

Stamp picture
Click here for higher resolution image
Click here to see FDC's		First day of issue: June 27, 2001
Width: 40 mm
Height: 26 mm
Perforation: Serpentine die cut 11.50 x 11.50
Printing method: Photogravure
Catalog number:
     Michel 3473
     Scott 3519
Location: Ice Hockey Volume CII
Stamp ID = 6626

Wrigley Field is a baseball stadium that hosted the 2009 NHL Winter Classic between the Chicago Blackhawks and the Detroit Red Wings. Detroit won, 6-4. The backing of the stamp had some printing as shown below

.

From Linn's "Stamp Issuing Entities Of The World" page.

United States of America (1847-)
Stamp-issuing status: active; Population: 248,709,873 (1990). Republic occupying the central portion of North America, along with Alaska, Hawaii and a large number of island possessions in the Caribbean Sea and the Pacific Ocean.