According to locke what is the source of a governments right to rule

Locke believed that in order to protect natural rights, government power had to be limited.

montesquieu took the view that the roman republic had powers separated so that no one could usurp complete power. in the british constitutional system, montesquieu discerned a separation of powers among the monarch, parliament, and the courts of law.

do you have a list of sources to choose from?