Does IAS require consolidated accounts reported for subsidiary companies pursuing dissimilar activities (than those of the parent company)?

Can you quote the relevant IASs?  Where can I find copies and guidelines of the IASs for reading?

Do EU companies have to follow IAS since 2005?  What other standards (e.g. IFRS) are acceptable?  In which legislations?

Reference

Corporate Financial Accounting and Reporting 2nd Ed by Tim Sutton