(16) http://commons.wikimedia.org/wiki/Image:
Temperate_rainforest_2004-04-09.jpg. GNU-FDL.
(17) http://commons.wikimedia.org/wiki/Image:
Terrestrial_planet_size_comparisons.jpg. GNU-FDL.
(18) http://commons.wikimedia.org/wiki/Image:Europasaurus_holgeri_detail.png.
GNU-FDL.
(19) http://commons.wikimedia.org/wiki/Image:Earth_layers_model.png.
GNU-FDL.
(20) http://commons.wikimedia.org/wiki/Image:
Ursus_maritimus_4_1996-08-04.jpg. GNU-FDL.
(21) Charles Doolittle Walcott.. GNU-FDL.
(22) http://commons.wikimedia.org/wiki/Image:As08-16-2593.jpg. GNU-FDL.
