Human Papilloma Vaccines: Questions & Answers (2018). National Cancer Institute Member Services.
芝加哥风格引文Human Papilloma Vaccines: Questions & Answers (2018). National Cancer Institute Member Services.
MLA引文Human Papilloma Vaccines: Questions & Answers (2018). National Cancer Institute Member Services.
警告：这些引文格式不一定是100％准确.