3898748

Information

• Patent Grant
• 3898748

• References
• Source

• Patent Number

  3,898,748

• Date Filed

  Not available

• Date Issued

  Tuesday, August 12, 1975
  49 years ago

• CPC

  • G09B11/08 - Teaching shorthand
  • G09B13/00 - Teaching typing

• US Classifications

  • 434 - Education and demonstration