Items

• [E1565RG1], Letter from West Orange Laboratory to Helen Augusta Hayes, December 29th, 1915
  1915-12-29
• [F5F06AO], Letter from Mina Miller (Mrs Thomas A.) Edison to Helen Augusta Hayes, November 13th, 1916
  1916-11-13
• [LB097066], Letter from Thomas Alva Edison to Helen Augusta Hayes, February 20th, 1914
  1914-02-20