APA (7th ed.) Citation

Wald, M. L. Questions about a hydrogen economy. [article]. 5 /p.40-47 My 2004.

Chicago Style (17th ed.) Citation

Wald, Matthew L. Questions About a Hydrogen Economy. [article]. v.290: 5 /p.40-47 My 2004.

MLA (9th ed.) Citation

Wald, Matthew L. Questions About a Hydrogen Economy. [article]. 5 /p.40-47 My 2004.