Contents 1. Introduction 2 2. Preliminaries 4 2.1. Some results on ...

170) ) (χ= ρ ◦(p QB ̂QA ◦(Qpb Q◦ χ ̂Q)A U ◦ (QP Ql A U) ◦ (QP QP x A U)) ) ( ) ((193)= ρ ◦(p QB ̂QA ◦(Qpb Q◦ Q B µb Q AU ◦ Qy ̂Q)A U ◦ (QP Ql A U))y= ρ ◦(p QB ̂QA(149)= ρ ◦◦ (QP QP x A U)) ( )◦(Qpb Q◦ Q B µb Q AU ◦ (QBl A U) ◦ (QBP x A U) ◦ (QyP QP A U)) ) ( )(p QB ̂QA ◦(Qpb Q◦ Q B µb Q AU ◦ (QBν 0AU) ′ ◦ (QByP A U)◦ (QyP QP A U)) )(151)= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Qν 0AU) ′ ◦ (Qm B P A U) ◦ (QByP A U)◦ (QyP QP A U)) )= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Qν 0AU) ′ ◦ (Qm B P A U) ◦ (QyyP A U)) )(109)= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Qν 0AU) ′ ◦ (QyP A U) ◦ (QP χP A U)) )(149)= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Ql A U) ◦ (QP x A U) ◦ (QP χP A U)) )(102)= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Ql A U) ◦ (QP m AA U) ◦ (QP xx A U)) )= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Ql A U) ◦ (QP m AA U) ◦ (QP xA A U) ◦ (QP QP x A U)) ) ( )(150)= ρ ◦(p QB ̂QA ◦(Qpb Q◦ Qµ A Q bAU◦ (QlA A U) ◦ (QP xA A U) ◦ (QP QP x A U)defp bQ( ) )= ρ ◦ p QB ̂QA ◦(Qpb Q◦(Q ̂Q)A Uλ A ◦ (QlA A U) ◦ (QP xA A U) ◦ (QP QP x A U)) )l= ρ ◦(p QB ̂QA ◦(Qpb Q◦ (Ql A U) ◦ (QP A A Uλ A ) ◦ (QP xA A U) ◦ (QP QP x A U)(203)= ( A Uλ A ) ◦ (m AA U) ◦ (xA A U) ◦ (QP A A Uλ A ) ◦ (QP xA A U) ◦ (QP QP x A U)x= ( A Uλ A ) ◦ (m AA U) ◦ (AA A Uλ A ) ◦ (xAA A U) ◦ (QP xA A U) ◦ (QP QP x A U)m A= ( A Uλ A ) ◦ (A A Uλ A ) ◦ (m A A A U) ◦ (xAA A U) ◦ (QP xA A U) ◦ (QP QP x A U)AUλ A ass= ( A Uλ A ) ◦ (m AA U) ◦ (m A A A U) ◦ (xAA A U) ◦ (QP xA A U)m A ass= ( A Uλ A ) ◦ (m AA U) ◦ (Am AA U) ◦ (xAA A U) ◦ (QP xA A U)AUλ A ass= ( A Uλ A ) ◦ (A A Uλ A ) ◦ (Am AA U) ◦ (xAA A U) ◦ (QP xA A U)= ( A Uλ A ) ◦ (A A Uλ A ) ◦ (Am AA U) ◦ (AxA A U) ◦ (xQP A A U)) )(203)= ( A Uλ A ) ◦ (Aρ) ◦(Ap QB ̂QA ◦(AQpb Q◦ (AQl A U) ◦ (xQP A A U))x= ( A Uλ A ) ◦ (Aρ) ◦(Ap QB ̂QA ◦(xQ ̂Q) )A ◦(QP Qpb Q◦ (QP Ql A U)