The justification of the assertion of the burgomasters and Senate of the city of Amsterdam, concerning the illegality of Monsieur Bentingh, the present Earl of Portland, &c. his sitting in the assembly of the lords states of Holland and West-Friesland : tending withal to the refutation of what has been alledged against them by the lords of the Ridderschap and nobles : together with the lords and deputies of the respective cities, upon the 20th of January last, and the deduction thereupon ensuing.