I took these photo today to see what the differences might be between these 3 semps.
'Bernstein' by Botanical Garden T�bingen 1972
'Gelber Stern' by Horst Diehm 2003
'Tederheid' by Gustaaf Van Der Steen 1978
All three seem to have the same long pink stolons. 'Gelber Stern' has deeper coloring this time of year. All seem to have a velvety texture and thicker leaves.
'Tederheid' has grown better for me than 'Berstein', both grown in the same conditions. But I must say these two look very much like each other.