- Adam Joseph's Freethoughts.
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- Correx
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- Critiques of Libertarianism
- CSICOP
- Donald Simanek
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- European Council of Skeptical Organisations
- Inquiring Skeptics of Upper New York (ISUNY)
- Korea PseudoScience Awareness (in Korean)
- Mike Hutchinson Books
- National Center for Science Education
- National Council Against Health Fraud
- New Zealand Rationalists and Humanists
- New Zealand Skeptics
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- Numberwatch
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- Tampa Bay Skeptics
- UFOs: A Skeptical View
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- Urban Legends Reference Page
- US Skeptics' Society
- Vetenskap och Folkbildning
