Real-Time Transmission of Coherent Pluggable-Based Super-Channels over 1500-km with 6.06-b/s/Hz Spectral Efficiency using Digital Subcarriers. - Amir Rashidinejad; A. Mathur; T. Gerard; Jacqueline Sime; M. Sezer Erkilinc; Thomas Duthel; Aditya Kakkar; J. M. Buset; C. R. S. Fludger; R. Maher (OFC, 2025)