Registered cover franked with 17c red, blue & grey and 36c scarlet, yellow & black 'Closure of the 7th Pan-American Conference' TRIANGLE issue (SG 714/715) tied by special commemorative cancels dated 1 JAN 1934 with registration label alongside and MONTEVIDEO cds. Addressed to ROCHA with arrival cds on reverse. A very scarce commemorative issue on cover.