StataCorp LP. Mata reference manual: Release 9.
Cita Chicago (17th ed.)StataCorp LP. Mata Reference Manual: Release 9.
Cita MLA (9th ed.)StataCorp LP. Mata Reference Manual: Release 9.
Atenció: Aquestes cites poden no estar 100% correctes.
StataCorp LP. Mata reference manual: Release 9.
Cita Chicago (17th ed.)StataCorp LP. Mata Reference Manual: Release 9.
Cita MLA (9th ed.)StataCorp LP. Mata Reference Manual: Release 9.