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\cite{poussin,cruz,many,strange,unused}

a: \natcite[empty][prenote][postnote]{poussin,cruz,many,strange,unused}
b: \natcite[empty][][]{poussin,cruz,many,strange,unused}
d: \natcite[][][post]{poussin,cruz,many,strange,unused}
e: \natcite[][pre][]{poussin,cruz,many,strange,unused}
f: \natcite[][pre][]{poussin}

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