Note 3590 — THE JULIAN CALENDAR AND THE CHRONOLOGY OF CAESAR’S INVASIONS OF BRITAIN
Reading edition
De die natali, xx, 4, § 10.—Praeterea pro quadrante diei, qui annum verum suppleturus videbatur, instituit, ut peracto quadrienni circuitu dies unus, ubi mensis quondam solebat, post Terminalia intercalaretur.