preparation of some diethyl substituted phenyl phosphates / P.R. Avis and H.L. Boter ; uitg. R.V.O./T.N.O. Chemisch Laboratorium Syntheses and toxicities of some series of choline-sterase inhibiting agents... / H.L. Boter ; uitg. R.V.O./T.N.O. Chemisch Laboratorium Separation of imidazole and its N-methyl derivatives on polyamide thin layers / A. Verweij ; uitg. R.V.O./T.N.O. Chemisch Laboratorium Concentrating dilute aerosols by electrostatic methods / J.F. van der Wal ; uitg. R.V.O./T.N.O. Chemisch Laboratorium Rapport betreffende de vergelijking tusschen drie verschillende geweren : 9 april 1789 / B.E. Paravicini di Capelli resolution of some O-alkyl hydrogen methylphosphonothioates / H.L. Boter ; uitg. R.V.O./T.N.O. Chemisch Laboratorium Isolation of active fractions from Manzanilla latex / B.P. Timmer ; uitg. R.V.O./T.N.O. Chemisch Laboratorium use of semi-micro techniques in infrared spectroscopy / F.H. Meppelder ; uitg. R.V.O./T.N.O. Chemisch Laboratorium analysis of adsorption isotherms of vapours on homogeneous surfaces / J.G.T. van Aken ; uitg. R.V.O./T.N.O. Chemisch Laboratorium Multilayer adsorption on carbon adsorbents / J.G.T. van Aken Review of the medical problems encountered in deep sea diving / E. Meeter efficiency of electrostatic air filters in a SPF rat breeding unit / J.L.F. Gerbrandy, D. van der Waay and H.C. Bartlema