About the existing discrepancy in the determinations of the Avogadro constant. - Jens Martin; Horst Bettin; Ulrich Kuetgens; Detlef Schiel; Peter Becker 003 (IEEE Trans. Instrum. Meas., 1999)

A reassessment of the molar volume of silicon and of the Avogadro constant. - Paul De Bievre; Staf Valkiers; Rüdiger Kessel; P. D. P. Taylor; Peter Becker 003; Horst Bettin; Anna Peuto; S. Pettorruso; Kenichi Fujii; Atsushi Waseda; Mitsuru Tanaka; R. D. Deslattes; et al. (IEEE Trans. Instrum. Meas., 2001)

Flotation measurements to reveal the reason for the discrepancy in the molar volume of silicon. - Horst Bettin; Hans Toth (IEEE Trans. Instrum. Meas., 2003)

Comparison of density difference measurements at PTB and NMIJ. - Horst Bettin; Hans Toth; Atsushi Waseda; Kenichi Fujii (IEEE Trans. Instrum. Meas., 2005)

Present State of the avogadro constant determination from silicon Crystals with natural isotopic compositions. - Kenichi Fujii; Atsushi Waseda; Naoki Kuramoto; Shigeki Mizushima; Peter Becker 003; Horst Bettin; R. Arnold Nicolaus; Ulrich Kuetgens; Staf Valkiers; Philip Taylor 001; Paul De Bievre; Giovanni Mana; et al. (IEEE Trans. Instrum. Meas., 2005)

Density Determination of a Small Isotopically Enriched Silicon Single Crystal. - Horst Bettin; Hans Toth (IEEE Trans. Instrum. Meas., 2007)

Oxide Layer Mass Determination at the Silicon Sphere of the Avogadro Project. - Ingo Busch; Hans-Ulrich Danzebrink; Michael Krumrey; Michael Borys; Horst Bettin (IEEE Trans. Instrum. Meas., 2009)

Current State of Avogadro 28Si sphere S8. - R. Arnold Nicolaus; Guido Bartl; Horst Bettin; Michael Borys; Martin Firlus; Ingo Busch; Andre Felgner; Rolf Kruger-Sehm; Michael Krumrey; Michael Krystek; Ulrich Kuetgens (IEEE Trans. Instrum. Meas., 2013)