He was born in Christiania to engineer Halvor Emil Heyerdahl and Alma Hedrich , and was married to Borghild Strugstad , daughter of Oscar Sigvald Julius Strugstad and sister of Oscar Sigvald Strugstad .
Head entity: oscar sigvald strugstad Q7106253 30 31 32
Tail entity: oscar sigvald julius strugstad Q7106259 23 24 25 26
Relation (head \u2192 tail): P40
Inverse relation (tail \u2192 head): P22