1. [1] Agmon, Shmuel On positivity and decay of solutions of second order elliptic equations on Riemannian manifolds, Methods of functional analysis and theory of elliptic equations (Naples, 1982), Liguori Editore, 1982, pp. 19-52
2. [2] Akutagawa, Kazuo Yamabe metrics of positive scalar curvature and conformally flat manifolds, Differ. Geom. Appl., Volume 4 (1994) no. 3, pp. 239-258
3. [3] Auscher, Pascal; Coulhon, Thierry; Duong, Xuan Thinh; Hofmann, Steve Riesz transform on manifolds and heat kernel regularity, Ann. Sci. Éc. Norm. Supér., Volume 37 (2004) no. 6, pp. 911-957
4. [4] Bakry, Dominique Étude des Transformations de Riesz dans les variétés Riemanniennes à courbure de Ricci minorée, Séminaire de probabilités XIX (Lecture Notes in Mathematics) Volume 1247, Springer, 1983, pp. 145-174
5. [5] Brüning, Jochen; Güneysu, Batu Heat kernel estimates and the relative compactness of perturbations by potentials (2016) (https://arxiv.org/abs/1606.00651)