when pigs fly

adv.

永无可能；

when pigs fly
When Pigs Fly
When Pigs Fly
When Pigs Fly: Immunomagnetic separation facilitates rapid determination of Pig-a mutant frequency by flow cytometric analysis
When pigs fly. Confronting the new era of disease transmission
When pigs fly, UCP1 makes heat
Campus commons: When pigs fly: A new perspective on learning
When pigs fly: the avian origin of a ‘swine flu’
When pigs fly: the avian origin of a ‘swine flu’
When PIGs Fly - addressing software reliability concerns for the IRIS IP router operating system
When pigs fly? Legal and ethical issues in transgenics and the creation of chimeras. The Walter C. Randall Biomedical Ethics Lecture.
When Pigs Fly: Anime, Auteurism, and Miyazaki’s Porco Rosso
When Pigs Fly, part Two