Carl Friedrich Gauss¿s textbook, Disquisitiones arithmeticae, published in 1801 (Latin), remains to this day a true masterpiece of mathematical examination.                                                                                                                                 .

Congruent Numbers in General.- Congruences of the First Degree.-  Residues of Powers.- Congruences of the Second Degree.- Forms and Indeterminate Equations of the Second Degree.- Various Applications of the Preceding Discussions.- Equations Defining Sections of a Circle.- Additional Notes.- Tables.- Gauss' Handwritten Notes.- List of Special Symbols.- Directory of Terms.