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diff --git a/src/Coxeter_triangulation/include/gudhi/Functions/Function_lemniscate_revolution_in_R3.h b/src/Coxeter_triangulation/include/gudhi/Functions/Function_lemniscate_revolution_in_R3.h
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+++ b/src/Coxeter_triangulation/include/gudhi/Functions/Function_lemniscate_revolution_in_R3.h
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+/*    This file is part of the Gudhi Library. The Gudhi library
+ *    (Geometric Understanding in Higher Dimensions) is a generic C++
+ *    library for computational topology.
+ *
+ *    Author(s):       Siargey Kachanovich
+ *
+ *    Copyright (C) 2019 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef FUNCTIONS_FUNCTION_LEMNISCATE_REVOLUTION_IN_R3_H_
+#define FUNCTIONS_FUNCTION_LEMNISCATE_REVOLUTION_IN_R3_H_
+
+#include <gudhi/Functions/Function.h>
+#include <Eigen/Dense>
+
+namespace Gudhi {
+
+namespace coxeter_triangulation {
+
+/** 
+ * \class Function_lemniscate_revolution_in_R3 
+ * \brief A class that encodes the function, the zero-set of which is a surface of revolution
+ * around the x axis based on the lemniscate of Bernoulli embedded in R^3.
+ *
+ * \ingroup coxeter_triangulation
+ */
+struct Function_lemniscate_revolution_in_R3 : public Function {
+
+  /** 
+   * \brief Value of the function at a specified point.
+   * @param[in] p The input point. The dimension needs to coincide with the ambient dimension.
+   */
+  Eigen::VectorXd operator()(const Eigen::VectorXd& p) const {
+    double x = p(0)-off_[0], y = p(1)-off_[1], z = p(2)-off_[2];
+    Eigen::VectorXd result(cod_d());
+    double x2 = x*x, y2 = y*y, z2 = z*z, a2 = a_*a_;
+    double t1 = x2 + y2 + z2;
+    result(0) = t1*t1 - 2*a2*(x2 - y2 - z2);
+    return result;
+  }
+
+  /** \brief Returns the (ambient) domain dimension.*/
+  std::size_t amb_d() const {return 3;};
+
+  /** \brief Returns the codomain dimension. */
+  std::size_t cod_d() const {return 1;};
+
+  /** \brief Returns a point on the surface. This seed point is only one of 
+   * two necessary seed points for the manifold tracing algorithm.
+   * See the method seed2() for the other point. 
+   */
+  Eigen::VectorXd seed() const {
+    Eigen::Vector3d result(sqrt(2*a_)+off_[0], off_[1], off_[2]);
+    return result;
+  }
+
+  /** \brief Returns a point on the surface. This seed point is only one of 
+   * two necessary seed points for the manifold tracing algorithm. 
+   * See the method seed() for the other point. 
+   */
+  Eigen::VectorXd seed2() const {
+    Eigen::Vector3d result(-sqrt(2*a_)+off_[0], off_[1], off_[2]);
+    return result;
+  }
+  
+  /** 
+   * \brief Constructor of the function that defines a surface of revolution
+   * around the x axis based on the lemniscate of Bernoulli embedded in R^3.
+   *
+   * @param[in] a A numerical parameter.
+   * @param[in] off Offset vector.
+   */
+  Function_lemniscate_revolution_in_R3(double a = 1,
+				       Eigen::Vector3d off = Eigen::Vector3d::Zero())
+    : a_(a), off_(off) {}
+
+protected:
+  double a_;
+  Eigen::Vector3d off_;
+};
+
+} // namespace coxeter_triangulation
+
+} // namespace Gudhi
+
+
+#endif