Optimal quadrature formulas with positive coefficients in L2(m)(0,1) space

In the Sobolev space L2(m)(0,1) optimal quadrature formulas of the form ∫01φ(x)dx≅∑β=0NCβφ(xβ) with the nodes xi=ηih,xN−i=1−ηih,i=0,t−1¯,0≤η0<η1<⋯<ηt−1