New perspectives on calcium environments in inorganic materials containing calcium–oxygen bonds: A combined computational–experimental 43Ca NMR approachChristel Gervais; Danielle Laurencin; Alan Wong; Frédérique Pourpoint; John Labram; Bleddyn Woodward; Andrew P. Howes; Kevin J. Pike; Ray Dupree; Francesco Mauri; Christian Bonhomme; Mark E. Smith · 2008