a blind letter

a circular letter

a letter

a letter sent as thanks for being treated well as someone’s guest

acceptance letter of credit

accepted letter of credit

accompanying letter

advice of transfer of letter of credit

Advisory Letter

advisory letter [slope maintenance]

air letter

amend a letter of credit

application for letter of credit

Approval letter

assignable letter of credit

bank guarantee letter

bank letter of credit

blackface letter

business letter

Circular letter