‘KONINKLI JKE AKADEMIE 
VAN WETENSCHAPPEN 
-- TE AMSTERDAM -:- 
PROCEEDINGS OF THE 
SoeON OF SCIENCES 
5.06(49.2) A5 
VOLUME XXII 
— (187 PART) — 
— (N°. 1—5) — 
JOHANNES MULLER :—: AMSTERDAM 
FEBRUARY 1920 
