Non-profit limited company
"Manash Kozybayev
North Kazakhstan university"
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Quotation gallery

To know that we know what we know, and that we do not know what we do not know, that is true knowledge.

Henry David Thoreau

Олимпиада учителей химии

19.02.2013 Проведена областная олимпиада учителей химии.

11.03.2013