The phrase "of obstinacy" is grammatically correct and can be used in written English.
It is often used to describe a person's behavior or attitude of being stubborn and refusing to change. Here is an example sentence: "Despite their parents' attempts to reason with them, the child's display of obstinacy remained unchanged."
He shares with them the virtue of obstinacy.
Reluctance to modify mortgages isn't always a matter of obstinacy or ineptitude.
It takes a peculiar form of obstinacy for news channels such as the BBC to consistently not mention climate change.
Like him, she combines eerie understatement with a core of obstinacy and a determination to dissolve formulas.
The symphonies of the Danish composer Rued Langgaard suggest a third path: one of obstinacy and a touch of perversity.
And among local folk, the refrain "Montauk is still Montauk" is heard these days with a bit of obstinacy.
During a period of 15 months (June 2000 August 2001), are enrolled all the patients presenting a septic shock requiring high and/or increasing doses of vaso-active agents because of the obstinacy of a low blood pressure in spite of a satisfactory colloid infusion.
The lapidary employs three principal tests for the determination of values, viz.: the fusibility of a gem, with or without a flux; its behavior before the blowpipe, and the action of acids upon it Sometimes, these tests are ineffectual, in consequence of the obstinacy of certain stones which will yield to nothing, and so must perforce be ranked among the first-rates.
The deal is now unraveling because of the obstinacy of Honduras's ousted president, Manuel Zelaya, and the man who ousted him, Roberto Micheletti.
The Communist newspaper "L'Humanite" covering the meeting of the Big Four in Paris said recently "If the debates seem monotonous, it is because of the obstinacy of the Westerners.
Hopley claimed to be a paedagogical follower of John Locke, who had decried the use of corporal punishment except in cases of extreme obstinacy on the part of the student.
