投标保函 TENDER GUARANTEE ; bid bond ; Bid security ; Bid Guarantee

投函举报 report by letter

投标函 bid letter ; Letter of Tender ; Tender letter

投标邀请函 invitation for bid

投影函数 [数] projection function ; Integral Projection Function

投标函附录 Appendix to Tender

信函投标售币 mail-bid sale

投诉函 Complaints

接受投标信函 letter of acceptance

投标邀请书函 Invitation for Bid