The link to the CC-BY-SA license is http://creativecommons.org/licenses/by-sa/3.0/deed. instead of http://creativecommons.org/licenses/by-sa/3.0/deed (remove punctuation).
The link to the CC-BY-SA license is http:// creativecommons .org/licenses/ by-sa/3. 0/deed. instead of http:// creativecommons .org/licenses/ by-sa/3. 0/deed (remove punctuation).