{HEAD ~ The invention} provides {TAIL ~ a method} of making β alumina by heating aluminium oxide in the presence of Na2 O 
{ HEAD ~ The invention } provides { TAIL ~ a method } of making β alumina by heating aluminium oxide in the presence of Na2 O
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH