1970 SPACE EXPLORATION / APOLLO 13 letter with additional-printing Apollo 13 to USA, with Pof.1598, CDS PRAGUE 120/ 11.IV.70, sent back with sheetlet "Mailing was/were returned postal office Kennedy Space Center, protože APOLLO 13 nepřistálo on the Moon" + CDS PRAGUE 120/ 19.X.70; good condition