Cramér, Harald. "Preface". Mathematical Methods of Statistics (PMS-9), Volume 9, Princeton: Princeton University Press, 1946, pp. vii-x. https://doi.org/10.1515/9781400883868-001
Cramér, H. (1946). Preface. In Mathematical Methods of Statistics (PMS-9), Volume 9 (pp. vii-x). Princeton: Princeton University Press. https://doi.org/10.1515/9781400883868-001
Cramér, H. 1946. Preface. Mathematical Methods of Statistics (PMS-9), Volume 9. Princeton: Princeton University Press, pp. vii-x. https://doi.org/10.1515/9781400883868-001
Cramér, Harald. "Preface" In Mathematical Methods of Statistics (PMS-9), Volume 9, vii-x. Princeton: Princeton University Press, 1946. https://doi.org/10.1515/9781400883868-001
Cramér H. Preface. In: Mathematical Methods of Statistics (PMS-9), Volume 9. Princeton: Princeton University Press; 1946. p.vii-x. https://doi.org/10.1515/9781400883868-001