IK 3 fighters failed completely in defense of Prague but did their best in defending Belgrade. Here is the list of all Yugoslav claims in April War. 161.E and 162.E were equipped with this plane so look for this designation in the third column. I had prepared a English version of the table years ago, but haven't updated the site for a long long long time.
http://vvkj.airserbia.com/index.php?...ta_pobeda_vvkj