Mr. Nguyễn Ngọc Vỹ, the director of the Stamps Company (COTEVINA) - a member of the standing committee of the Philately Association of Việt Nam has sent the letter and presents to praise the Viet Stamp Club for contributions in the issue of the stampset “50th anniversary of the opening of the Hồ Chí Minh trail and the traditional day of the Trường Sơn troops (19-5-1959 – 19-5-2009)”.