In situ X-ray diffraction observation of two-step fullerene coalescence in carbon peapods C. Bousige, S. Rols, E. Paineau, S. Rouzière, C. Mocuta, H. Kataura and P. Launois EPL, 103 6 (2013) 66002 Published online: 22 October 2013 DOI: 10.1209/0295-5075/103/66002