The Koan "No"
- Teisho by Melissa Blacker, Sensei, Boundless Way Zen.
- http://www.boundlesswayzen.org/teishos/blacker-noteisho.html

Realm of Mu
- A dharma talk by Eido Shimano Roshi on Yamamoto Gempo Roshi's experience studying Mu.
- http://www.digitalzendo.com/?library&step=17

Joshu's Mu
- Excerpt from 'Golden Wind, Zen Talks' by Eido Shimano Roshi.
- http://www.digitalzendo.com/?library&step=28

Chao-chou's Dog
- Commentary by Barry Magid.
- http://www.ordinarymind.com/koan_chao.html

The Koan Mu
- A teisho by John Tarrant, Roshi.
- ftp://coombs.anu.edu.au/coombspapers/otherarchives/electronic-buddhist-archives/buddhism-zen/teachings/tarrant-john/tarrant-teisho-97-10-18.txt

Nothing from Nothing
- Mumon's own response to the first case of the Mumonkan.
- http://www.ubu.com/contemp/elgar/elgar1.html

Mumonkan Case I: Joshu's Dog
- from R.H. Blyth, "Zen and Zen Classics", Vol. 4, Mumonkan (1966).
- http://www.ubu.com/contemp/elgar/mukoan.htm

Dogen's Commentary on Joshu's Dog
- From the Shobogenzo.
- http://mindis.com/CONTENT/Dogen&MU.htm

The Zen Concept of Emptiness, or Mu.
- A lengthy definition of mu. FTP download text file.
- ftp://ftp.buddhanet.net/zenbud/mu.zip