Towards Outdoor Collaborative Mixed Reality: Lessons Learnt from a Prototype System. - Nels Numan; Ziwen Lu; Benjamin Congdon; Daniele Giunchi; Alexandros Rotsidis; Andreas Lernis; Kyriakos Larmos; Tereza Kourra; Panayiotis Charalambous; Yiorgos Chrysanthou; Simon Julier; Anthony Steed (VR Workshops, 2023)