APA (7th ed.) Citation

Billings, E. 9 Metode Ovulasi Billings: Cara Alami Mengatur Kesuburan/ Cet.3. Kepustakaan Populer Gramedia.

Chicago Style (17th ed.) Citation

Billings, Evelyn. 9 Metode Ovulasi Billings: Cara Alami Mengatur Kesuburan/ Cet.3. Kepustakaan Populer Gramedia.

MLA (8th ed.) Citation

Billings, Evelyn. 9 Metode Ovulasi Billings: Cara Alami Mengatur Kesuburan/ Cet.3. Kepustakaan Populer Gramedia.

Warning: These citations may not always be 100% accurate.