NIGER (1974) Infant*. Die proof in grey signed by the engraver COMBET. World population year. Scott No 207, Yvert No 301.
$40
CENTRAL AFRICA (1974) Stylized people*. Imperforate pair. World Population Year. Scott No 211, Yvert No 220.
$10
CENTRAL AFRICA (1974) Stylized people*. Trial color proof pair. World Population Year. Scott No 211, Yvert No 220.
$10
HUNGARY (1975) Environmental protection*. Set of 7 imperforates. Scott Nos 2375-81.
$25
NORTH KOREA (1977) Five-Point policy of nature harnessing. Specimen. Scott No 1569, KSC No 1578.
$5
MAURITANIA (1982) World Environment Day*. Imperforate. Scott No 514, Yvert No 510.
$5
NORTH KOREA (1982) Four nature-remaking tasks. Specimen. Scott No 2174, KSC No 2205.
$5
SWEDEN (1987) Clouded apollo*. Hermit beetle*. Field gentian*. Leopard's bane*. FDC. Scott Nos 1623-5, Yvert Nos 1406-9.
$4
NORTH KOREA (1992) Various animals and plants. World Environment Day. Set of 8 specimens. Scott Nos 3144-51, KSC Nos 3247-54.
$40
NORTH KOREA (1992) Endangered species*. Set of 8 overprinted SPECIMEN. KSC Nos 3247-54. Scott Nos 3144-51.
$40
TUVALU (1993) Greenhouse effect on sea and shore life. Set of 4 overprinted SPECIMEN. Scott Nos 648-52, Yvert Nos 637-40.
$40
NORTH KOREA (1993) Air pollution. M/S of 2 specimens. Scott No 3387, KSC No 3502.
$10
NORTH KOREA (1993) Water pollution. M/S of 2 specimens. Scott No 3388, KSC No 3503.
$10
NORTH KOREA (1993) Animal resources. M/S of 2 specimens. Scott No 3389, KSC No 3504.
$10
NORTH KOREA (1993) Forest resources. M/S of 2 specimens. Scott No 3390, KSC No 3505.
$10
NORTH KOREA (1994) World Environment Day*. Set of 4 minisheets (2 identical stamps each) overprinted SPECIMEN. KSC Nos 3501-4. Scott Nos 3387-90.
$40
F.S.A.T. (1990) Cattle*. FDC with cachet. Rehabilitation of the environment. Scott No 152, Yvert No 149.