| National Geographic Magazine February 1981 Vol. 159 #4Â |
| National Geographic Magazine FEBRUARY 1967 VOL 131 NO 2 |
| National Geographic Magazine 1926 Vol. 71 No.4 |
| National Geographic Magazine JUNE 1966 VOL 129 NO 6 |
| National Geographic Magazine 1988 Vol. 174 #6 |
| National Geographic Magazine, 1937 Vol. 71, No.5 |
| Nat'l. Geographic magazine, July 1955, Vol. CVIII, #1 |
| THE NATIONAL GEOGRAPHIC MAGAZINE DEC 1958 VOL CXIV No 6 |
| National Geographic Magazine Nov 1951 Vol C Number 5 |
| THE NATIONAL GEOGRAPHIC MAGAZINE MAR 1959 VOL CXV No. 3 |
| 1914 National Geographic Magazine Bound Vol 25 and 26 |
| National Geographic Magazine FEBRUARY 1966 VOL 129 NO 2 |
| THE NATIONAL GEOGRAPHIC MAGAZINE OCT 1959 VOL CXVI No 4 |
| National Geographic Magazine AUGUST 1967 VOL 132 NO 2 |
| National Geographic Magazine MARCH 1965 VOL 127 NO 3 |
| National Geographic Magazine SEPTEMBER 1967 VOL 132 No3 |
| National Geographic Magazine July, 1955 Vol. 108, No. 1 |
| THE NATIONAL GEOGRAPHIC MAGAZINE JUNE 1959 VOL CXV No 6 |
| National Geographic Magazine JULY 1966 VOL 130 NO 1 |
| National Geographic Magazine JULY 1967 VOL 132 NO 1 |
| 1950 NATIONAL GEOGRAPHIC Magazine BOOKS Vol 97 & 98 |
| THE NATIONAL GEOGRAPHIC MAGAZINE FEB 1959 VOL CXV No. 2 |
| NATIONAL GEOGRAPHIC MAGAZINE- VOL.124,NO.6- DEC.1963 |
| THE NATIONAL GEOGRAPHIC MAGAZINE AUG 1959 VOL CXVI No 2 |
| National Geographic Magazine October 1983 Vol 164 #4 NR |
| National Geographic Magazine July 1974 vol. 146 #1 |
| 1949 NATIONAL GEOGRAPHIC Magazine BOOKS Vol 95 & 96 |
| 1951 NATIONAL GEOGRAPHIC Magazine BOOKS Vol 99 & 100 |
| National Geographic Magazine 1924 Vol. 66 No.2 |
| THE NATIONAL GEOGRAPHIC MAGAZINE OCT 1958 VOL CXIV No 4 |
| National Geographic Magazine NOVEMBER 1966 VOL 130 NO 5 |
| National Geographic Magazine, 1939 Vol. 75 No.5 |
| The National Geographic Magazine April,1920 Vol 37 # 4 |
| National Geographic Magazine MARCH 1966 VOL 129 NO 3 |
| THE NATIONAL GEOGRAPHIC MAGAZINE JAN 1959 VOL CXV NO 1 |
| THE NATIONAL GEOGRAPHIC MAGAZINE APR 1959 VOL CXV No 4 |
| 1937 NATIONAL GEOGRAPHIC MAGAZINE BOOK, VOL. LXXII |
| 1937 NATIONAL GEOGRAPHIC MAGAZINE BOOK, VOL. LXXI |
| Nat'l. Geographic magazine, July 1955, Vol. CVIII, #1 |