Material/Constituent elements of seawater

Approximate composition of seawater by mass:

Element	% mass
Oxygen	85.7
Hydrogen	10.8
Chlorine	1.9
Sodium	1.05
Magnesium	0.14
Sulfur	0.09
Calcium	0.04
Potassium	0.04
Others	Trace

Figures from [1]
Need to find definitive primary source
Element links in list point to Wikipedia article