list-style-type: lower-alpha;
<div class="uk-child-width-1-2 uk-grid-small" uk-grid>
<div><img src=""></div>
<div class="uk-child-width-1-2 uk-grid-match uk-grid-small" uk-grid>
<div><img src=""></div>
<div><img src=""></div>
<div><img src=""></div>
<div><img src=""></div>
</div>
</div>