3673704

Information

• Patent Grant
• 3673704

• References
• Source

• Patent Number

  3,673,704

• Date Filed

  Not available

• Date Issued

  Tuesday, July 4, 1972
  52 years ago

• CPC

  • G09B1/24 - the elements being in flexible strip form
  • G09B19/06 - Foreign languages

• US Classifications

  • 434 - Education and demonstration