Campaign 74B
... that during Campaign 74B in the Laotian Civil War, smog from swidden farming clogged the air?
... that during <b id="mwBiU"><a href="./Campaign_74B" id="mwBiY" rel="mw:WikiLink" title="Campaign 74B">Campaign 74B</a></b> in the <a href="./Laotian_Civil_War" id="mwBic" rel="mw:WikiLink" title="Laotian Civil War">Laotian Civil War</a>, smog from <a href="./Slash-and-burn" id="mwBig" rel="mw:WikiLink" title="Slash-and-burn">swidden farming</a> clogged the air?