Reference for Eruvin 7:11
נוֹתֵן אָדָם מָעָה לְחֶנְוָנִי וּלְנַחְתּוֹם כְּדֵי שֶׁיִּזְכֶּה לוֹ עֵרוּב, דִּבְרֵי רַבִּי אֱלִיעֶזֶר. וַחֲכָמִים אוֹמְרִים, לֹא זָכוּ לוֹ מְעוֹתָיו. וּמוֹדִים בִּשְׁאָר כָּל אָדָם שֶׁזָּכוּ לוֹ מְעוֹתָיו, שֶׁאֵין מְעָרְבִין לְאָדָם אֶלָּא מִדַּעְתּוֹ. אָמַר רַבִּי יְהוּדָה, בַּמֶּה דְבָרִים אֲמוּרִים, בְּעֵרוּבֵי תְחוּמִין, אֲבָל בְּעֵרוּבֵי חֲצֵרוֹת, מְעָרְבִין לְדַעְתּוֹ וְשֶׁלֹּא לְדַעְתּוֹ, לְפִי שֶׁזָּכִין לְאָדָם שֶׁלֹּא בְּפָנָיו, וְאֵין חָבִין לְאָדָם שֶׁלֹּא בְּפָנָיו:
One may give money to a shopkeeper [who sells wine and dwells with him in the mavui] or to a baker [who sells loaves and dwells with him in the courtyard] to assign to him (a share in) the eruv [with his fellows, viz.: "If the men of the mavui come to buy wine from you for a partnership, or the men of the courtyard, to buy a loaf for the eruv, let me have a share in it."] These are the words of R. Eliezer. The sages say: His money does not acquire for him. [For money does not acquire until one pulls (the purchased object). And even if the shopkeeper provided an eruv for all the others and also assigned it to this one, it is not an eruv, for he did not intend to assign it to him as a gift, gratis, in the manner of those who assign eruvin, but that he acquire it for the money. But he does not acquire it, for money (without "pulling") does not acquire; so that he is found to have made an eruv with his money.] And they concur that with other men (i.e., not shopkeepers) his money does acquire it. [If the house-owner says to his neighbor: "Take this money and assign an eruv for me," and he went and did so, he (the house-owner) acquires the eruv. For since the (other) house-owner does not regularly sell loaves, the first intended only to make him a messenger, as if he had said: "Make an eruv for me."] For an eruv may be made for another only with his knowledge. [Therefore, in the instance of the shopkeeper, when he said to him: "Assign it to me," his intent was only to acquire it from him, and he did not depend upon him as a messenger. And money does not acquire, and there was no empowering, so that he (the shopkeeper) would be making an eruv for him without his knowledge.] R. Yehudah said: When is this so? With eruvei tchumin (Sabbath bound eruvin) [which can be a liability, for he loses on the other side (of the tchum), and he may not wish it. The halachah is in accordance with R. Yehudah.], but with courtyard eruvin, the eruv can be made with or without his knowledge. For a man may be benefitted (even) when he is not present, and he may not be made to incur a loss except when he is present.