In the Talmud Bavli there is no Gemara for Shekalim, but there is one in the Yerushalmi. However, there are Gemaras for other massekhtot in the Yerushalmi for which there are none in the Bavli, and these did not become part of the Daf Yom cycle. So why should Shekalim alone jump borders and be included in the study schedule for the Babylonian Talmud?

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