Analysis of information sources in references of the Wikipedia article "Hebrew calendar" in English language version.
limits, Qebi'oth [kevi'ot]
When the center of Jewish life moved from Babylonia to Europe during the 8th and 9th centuries CE, calculations from the Seleucid era became meaningless. Over those centuries, it was replaced by that of the anno mundi era of the Seder Olam. From the 11th century, anno mundi dating became dominant throughout most of the world's Jewish communities.
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