APA aipamena

Billings, E. (1988). The Billings method: Controlling fertility without drug or devices. Ballantine.

Chicago Style aipamena

Billings, Evelyn. The Billings Method: Controlling Fertility Without Drug or Devices. Ballantine, 1988.

MLA aipamena

Billings, Evelyn. The Billings Method: Controlling Fertility Without Drug or Devices. Ballantine, 1988.

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