| Mathematics | New Zealand/Aotearoa |
| Books and course notes. | Wilderness photos |
| Expository and research articles. | |
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| A representation of Grothendieck's vision of a pinned reductive group. | Rakiura |
| World's major mountain ranges | Michigan lakes and rivers |
| Wilderness photos | Wilderness photos |
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| Kangchenjunga 8586m/28169ft (in distance at left) and Makalu 8475m/27806ft, from the northeast ridge of Everest May 18, 2004. |
Seney Wildlife Refuge, Upper Peninsula |
| Iceland | China |
| Photos of fiords, waterfalls, glaciers, ... | Photos of the West Lake Scenic Area and Huang Shan |
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| Kerlingarfjöll | The botanical gardens, Hangzhou, after a late snowfall, March 11, 2005. |