[David]

Well, you might have some trouble locating a copy of Kris Disk. They come up on eBay every now and then, but AFAIK it's out-of-print.
I lifted the following list off Alan Maisey's website. Not all these works are perfect, but they can all be valuable references in one way or another.
Off this list i would particularly recommend The World of the Javanese Keris (#3) and The Javanese Kris by Groneman (#21).
You will also find great value in reading material about the related culture. I highly recommend Margret Wiener's Visible and Invisible Realms for a perspective on Bali.

1. Krisses-A critical Bibliography-David van Duuren.Pictures Publishers,Polstraat 52,4261
BV,Wijk en Aalburg,Holland.I highly recommend this book.
2. Keris Jawa-antara Mystik dan Nalar-Haryono Haryoguritno- P.T. Indonesia
Kebanggaanku-Jakarta, ISBN: 979-25-2530-0. Text in Indonesian.
The most beautiful book on the keris that has ever been published.
3. The World of the Javanese Keris-Garrett and Bronwen Solyom,East-West
Centre-Hawaii,1978. An enormous amount of solid information in a limited number of pages.
This book has my complete endorsement.
4. Ensiklopedi Keris- Bambang Harsrinuksmo, Gramedia- Jakarta, ISBN:
979-22-0649-3.Text in Indonesian; a comprehensive reference.
5. The Kris-An Earthly Approach to a Cosmic Symbol-David van Duuren.Pictures Publishers
Polstraat 52,4261 BV,Wijk en Aalburg,Holland. An excellent book for beginners; I highly
recommend this book.
6. 'Origin of the Keris and its Development to the 14th. Century'-A.Maisey(article)
Published in "Arms Cavalcade"-The Official Journal of the Antique Arms Collectors Society of
Australia ,Vol.I,No.2, April 1998.
7. "An Interpretation of the Pre-Islamic Javanese Keris"- A.Maisey (article)
Published in "Arms Cavalcade"- The Official Journal of the Antique Arms Collectors Society of
Australia Co-op Limited, May 2013 ISSN 1325-779X
8. De Kris-Magic Relic of Old Indonesia-Vols.I,II and III Ing. G.J.F.J. Tammens.Holland,
1992/1993/1994.Parallel text in English and Dutch.
9. Origin of Early Kerises-Martin Kerner A4,152p.,50 ill.in black/white,ISBN 3-9520980-9-4
10. A Glossary of the Construction,Decoration ,and Use of Arms and Armour-George Cameron
Stone .(Several editions.The standard reference on Eastern Edged Weaponry).AKA-"Stones
Glossary"
11. The Keris and Other Malay Weapons-A.H.Hill,Journal of the Malay Branch of the Royal
Asiatic Society,Vol.XX Part II,1947.
12. The Kris-E.Frey,Oxford University Press,Singapore.
13. Keris-Drs.Hamzuri,P.T. Midas Surya Grafindo-Jakarta,1984.
14. Keris and Other Weapons of Indonesia-Moebirman,Yayasan Pelita Wisata,Jakarta,1973.
15. The Invincible Krises 2- Vanna Ghiringhelli, Saviolo Publisher, USA, 2007,
ISBN 978-88-95125-05-3
16. Kris the Invincible(Kris Gli Invincibili)-Vanna e Mario Ghiringheli,Be-Ma Editrice,Milano
1991.
17. 'An Introduction to the Javanese Keris'-Hardiono H.B.(article). Published in "Arts of
Asia",Vol.9,No.3 May-June 1979, 1309 Kowloon Centre,29-30 Ashley Road,Kowloon H.K.
18. The Keris and the Naga-A.G.Maisey(article). Published in "Arms Cavalcade"-The Official
Journal of the Antique Arms Collectors Society of Australia,Vol.I,No.3,December 2000.
19. 'The Great Blades of Java'-A.Maisey (article). Published in "Knives '90" DBI Books Inc.
Northfield,Illinois
20. The Keris in the Magic World View-Martin Kerner A4,62p.,ill. black/white.ISBN
3-9520980-2-7,1999
21. The Javanese Keris-Isaac Groneman, C.Zwatenkot Art Books, Leiden, 2009.
ISBN 978-90-5450-006. A collection of articles on the keris, including the landmark papers by
Isaac Groneman, immensely valuable from the historical perspective of study of the keris.