This template is a self-reference and so is part of the Wikipedia project rather than the encyclopaedic content.
This template accepts three parameters:
{{Wikisourcelang|1|2|3|4}}
{{Wikisourcelang-inline}}
{{wikisource}}
—to create the sidebox{{wikisource-inline}}
—to create a list of sources on Wikisource among other options{{cite wikisource}}
—to create a full citation to wikisource{{ws}}
—to place a wikisource icon before text, or a link to wikisource, or another template{{Wikisourcehas}}
—for allowing the including editor to choose the wording{{User Wikisource}}
—a Wikipedia userbox{{Wikisource redirect}}
—a specialized template for redirecting to Wikisource{{Wiktionarylang}}
—analogous to Wikisourcelang, but designed for terms in foreign language Wiktionary sites