BasisUrl = http://example.org/a/b/c/d/e/y.html

http://example.org/x/../../../../../x.htm = http://example.org/x/../../../../../x.htm
../../../../../x.htm = http://example.org/x.htm
../x.htm = http://example.org/a/b/c/d/x.htm
././../././../../x.htm = http://example.org/a/b/x.htm
././../././../.././../.././../.././../../../x.htm = http://example.org/../../../../../x.htm