I'm writing a short paper on macroeconomics; the professor gave us two tries, I submitted the first try, and now got my feedback.
The feedback is: "The first paragraph could also deserve a reference".
And these are the two paragraphs this refers to (note the reference  in the end):
Both rational ignorance and expressive voting are more likely to occur when instrumental voting does not seem to bring any benefit to the citizen; i.e. an election where the candidates have similar prognoses should attract instrumental, rational voters, whereas a landslide election with an almost predictable outcome attracts less total voters, but more ignorant or expressive ones, because they feel that their vote will not have any instrumental, decisive value, hence can be used to express an opinion.
Assume a voter realizes that he will not tip the balance, and will not benefit from the enactment of the candidate's promises. He can also not be paid for his vote. But he is willing to vote, in order to express his support for democracy, or maybe his dissatisfaction by voting for protest party. If he enjoys the voting process itself, then he is not benefiting in an instrumental sense, but in an emotional one. If this joy exceeds the cost of voting, he is still rational in some broader sense. 
Note that the second paragraph, after the word "opinion", starts in the very next line, without any empty line or any additional distance in between.
The thing is, the reference at the end was intended to spread over both paragraphs, since they are both "covered" by this source; however I understand that this may not be obvious. But what shall I do? I cannot quote it, since it's not a quote; so shall I put the citation twice, one for each paragraph? Won't the same citation within 5 sentences seem unbeautiful, or is this a necessary evil?