Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
summon, summons (n., v.)
Usage problems arise only with the legal senses of the word summons. In the courts a summons is “a document requiring the receiver to appear.” Its plural is summonses. There is also a verb to summons, again restricted to legal matters: The counsel for the defense summonsed me to testify. He gave out three other summonses. The verb summon is a regular weak verb meaning simply “call”: He summons birds by imitating their calls. The usual noun made from it (other than the infinitive itself) is a gerund: Summoning all his nerve was not enough.
