“To these recommendations were appended a copy of the minority report.” A transposition of the sentence will show that the verb should be was, and not were. “A copy of the minority report was appended to these recommendations.”
Whenever the sentence is introduced by a phrase consisting in part of a noun in the plural, or several nouns in the singular or plural, and, especially, where the subject follows the verb; care must be taken to keep the nominative well in mind, so that the verb may be in strict accord with it.
When a verb has two or more nominatives it must be plural. These nominatives may or may not be connected by and or other connecting particle. The nominatives may consist of nouns or pronouns, either singular or plural, or they may be phrases.
“Washington and Lincoln were chosen instruments of government.”
“Judges and senates have been bought for gold,
Esteem and love were never to be sold.”—Pope.
“Art, empire, earth itself, to change are doomed.”— Beattie.
“You and he resemble each other.”
“To read and to sing are desirable accomplishments.”