1. Department of Physics, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
2. Network Dynamics, Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 Göttingen, Germany
3. Department of Physics, Technical University of Darmstadt, 64289 Darmstadt, Germany
4. Mechanics and Applied Mathematics Group, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India