B. Franchi, R. Serapioni, F. Serra Cassano:
Rectifiability and Perimeter in the Heisenberg Group
Math.Ann. Vol. 321, p. 479-531, 2001

B. Franchi, R. Serapioni, F. Serra Cassano:
Rectifiability and perimeter in step 2 groups
Mathematica Bohemica Vol. 127, N. 2, p. 219-228, 2002

B. Franchi, R. Serapioni, F. Serra Cassano:
Regular hypersurfaces, Intrinsic perimeter and implicit function theorem in Carnot groups
Comm. Analysis and Geometry (Accepted Paper) 2002

B. Franchi, R. Serapioni, F. Serra Cassano:
On the structure of finite perimeter sets in step 2 Carnot groups
J.Geom.Anal. Vol. 13, N. 3, p. 421-466, 2003

B. Franchi, R. Serapioni, F. Serra Cassano:
Regular submanifolds, graphs and area formula in Heisenberg groups
Advances in Mathematics (Accepted Paper) 2004

B. Franchi, R. Serapioni, F. Serra Cassano:
Intrinsic submanifolds, graphs and currents in Heisenberg groups
Lectures Notes of Seminario Interdisciplinare di Matematica Vol. 4, p. 23-38, 2005

B. Franchi, R. Serapioni, F. Serra Cassano:
Intrinsic Lipshitz graphs in Heisenebrg groups
J. Nonlinear and Convex Analysis (Accepted Paper) 2006

B. Franchi, R. Serapioni, F. Serra Cassano:
Differentiability of intrinsic Lipschitz functions within Heisenberg groups
(Submitted Paper) 2008

G. Arena, R. Serapioni:
Intrinsic regular submanifolds in Heisenberg groups are differentiable graphs
Calc.Var. and PDE (Accepted Paper) 2008

B. Franchi, M. Marchi, R. Serapioni:
Intrinsic Lipschitz Graphs Within Carnot Groups
(Preprint) 2013