Reference for Shekalim 4:1
הַתְּרוּמָה מֶה הָיוּ עוֹשִׂין בָּהּ, לוֹקְחִין בָּהּ תְּמִידִין וּמוּסָפִין וְנִסְכֵּיהֶם, הָעֹמֶר וּשְׁתֵּי הַלֶּחֶם וְלֶחֶם הַפָּנִים, וְכָל קָרְבְּנוֹת הַצִּבּוּר. שׁוֹמְרֵי סְפִיחִים בַּשְּׁבִיעִית, נוֹטְלִין שְׂכָרָן מִתְּרוּמַת הַלִּשְׁכָּה. רַבִּי יוֹסֵי אוֹמֵר, (אַף הָרוֹצֶה) מִתְנַדֵּב שׁוֹמֵר חִנָּם. אָמְרוּ לוֹ, אַף אַתָּה אוֹמֵר, שֶׁאֵינָן בָּאִין אֶלָּא מִשֶּׁל צִבּוּר:
The terumah [i.e., what they put into the baskets] — what did they do with it? They bought temidin (the daily burnt-offerings), mussafin (the additional offerings), their libations, the omer, the two loaves, the show-bread, and all the communal offerings [including the incense]. The watchers of after-growths on shevi'ith (the sabbatical year) take their pay from the terumah of the lishkah. [The "aftergrowths" are what grow of themselves from what was left of the harvest. Watchmen are paid to see to it that the poor do not pick them on the shevi'ith, and they are brought for the omer on Pesach and for the two loaves on Shavuoth, which come only from the new produce and from Eretz Yisrael. The watchmen may be paid from the terumah, for what is needed for the offering is as the offering itself in this regard.] R. Yossi says: If one wishes, he may donate his services as an unpaid watchman. [And even though he acquires the after-growths from hefker (renounced property) by watching them gratis and bringing them, so that they are his — R. Yossi holds that an individual offering can be converted to a communal one.] They said to him: Do you not agree that they (these offerings) may come only from the congregation? [And if he watched the after-growths gratis and brought them and acquired them, they are found not to come from the congregation (the rabbis holding that an individual offering cannot be converted to a communal one.) The halachah is in accordance with the sages.]