Attribution

This is an ideal attribution:

"Creative Commons 10th Birthday Celebration San Francisco" by tvol is licensed under CC BY 2.0

Because:

• Title? "Creative Commons 10th Birthday Celebration San Francisco"
• Author? "tvol" - linked to his profile page
• Source? "Creative Commons 10th Birthday Celebration San Francisco" - linked to original Flickr page
• License? "CC BY 2.0" - linked to license deed

The full article:
https://wiki.creativecommons.org/wiki/Best_practices_for_attribution