https://impact.ornl.gov/en/publications/low-energy-incommensurate-spin-excitations-in-superconducting-la1/
Low-energy incommensurate spin excitations in superconducting La1.85Sr0.15CuO4 - Oak Ridge National...
https://research.ibm.com/publications/observation-of-a-low-energy-infrared-anomoly-in-superconducting-la185sr015cuo4
Observation of a low-energy infrared anomoly in superconducting La1.85Sr0.15CuO4 for Physical...
Observation of a low-energy infrared anomoly in superconducting La1.85Sr0.15CuO4 for Physical Review B by Z. Schlesinger et al.