SPQR is an initialism from a Latin phrase, Senatus Populusque Romanus ("The Senate and People of Rome"), referring to the government of the ancient Roman Republic, and used as an official signature of the government. It appears on coins, at the end of documents made public by inscription in stone or metal, in dedications of monuments and public works, and was emblazoned on the standards of the Roman legions. The phrase appears many hundreds of times in Roman political, legal and historical literature, including the speeches of Marcus Tullius Cicero and the history of Titus Livius. Since the meaning and the words never vary, except for the spelling and inflection of populus in literature, Latin dictionaries classify it as a formula.