History of the Peloponnesian War
Thucydides
Thucydides. The history of the Peloponnesian War, Volume 1-2. Dale, Henry, translator. London: Heinemann and Henry G. Bohn, 1851-1852.
Nevertheless the Peloponnesians considered that the first convention with Tissaphernes, which had been concluded by Chalcideus, was defective, and not so much for their advantage [as for his]; and, consequently, while Theramenes was yet there, they concluded another, which was to the following effect:
The convention of the Lacedaemonians and the allies with King Darius, the sons of the king, and Tissaphernes, that there should be a treaty and friendship between them on these terms:
Whatever territory and cities belong to King Darius, or did belong to his father, or his ancestors, against these neither the Lacedaemonians nor the allies of the Lacedaemonians shall be permitted to proceed for the purpose of war, or for any harm: neither shall the Lacedaemonians, nor their confederates, exact tribute from these cities. Neither shall King Darius, or any states in the king's dominions, be allowed to proceed against the Lacedaemonians, or their allies, for the purpose of war or other injury.——Should the Lacedaemonians, or their allies, require any assistance from the king, or the king stand in need of any from the Lacedaemonians, or their allies;
to whatever they may gain each other's assent, that shall be right for them to do.——Both parties shall carry on in common the war against the Athenians and their allies;
and should they come to terms of peace, they shall both do so in common.