Atomic and nuclear properties of tungsten by the Particle Data Group (2009)

Official 2009 material table: pdg.lbl.gov/2009/AtomicNuclearProperties/HTML_PAGES/074.html . It gives the reference density $19.3\mathrm{g}\mathrm{c}{\mathrm{m}}^{-3}$. It is an external reference, not the historical NST examination Data Book and not a measured hot-filament density.