i) The more precisely you quote the blog, the more detailed/precise your attribution should be.

ii) As the need to verify the attribution rises, the more detailed/precise your attribution should be.

Note: because many blogs and online pages are transitory (they may be available on the Web for a short period of time), it may be wise to include a printed screen shot of the blog entry as an appendix, or cite to a semi-permanent online archive URL of the blog, such as archive.org.