Pedzisa mutsara unotevera: Jansen akakunda wekutanga wezvikamu zvaro zvitatu zveDutch National mu 1977-78 mwaka. Anokwikwidza paMakwikwi eISU mashanu, akapedza 17th pa1978 Europeans muStrasbourg, France; 18th pa1978 Worlds muOttawa, Ontario, Canada; 20th pa1979 Europeans muZagreb, Yugoslavia; 23rd pa1978 Europeans muStrasbourg, France; 18th pa1978 Worlds muOttawa, Ontario, Canada; 20th pa1979 Europeans muZagreb, Yugoslavia;
1979 Worlds muVienna, Austria; uye 18th pa 1980 Europeans muGothenburg, Sweden.