Full Idea
I have transferred the relation between the parts and the whole of the sentence to its reference, by calling the reference of the word part of the reference of the sentence, if the word itself is part of the sentence.
Gist of Idea
The reference of a word should be understood as part of the reference of the sentence
Source
Gottlob Frege (On Sense and Reference [1892], p.35)
Book Reference
Frege,Gottlob: 'Translations from the Writings of Gottlob Frege', ed/tr. Geach,P/Black,M [Blackwell 1980], p.65
A Reaction
Since Frege says the reference of a true sentence is simply to truth, words have reference insofar as they make contributions to attempts at stating truths.