Cathodoluminescence and Photoluminescence of YPO<sub>4</sub>:Pr<sup>3+</sup>, Y<sub>2</sub>SiO<sub>5</sub>:Pr<sup>3+</sup>, YBO<sub>3</sub>:Pr<sup>3+</sup>, and YPO<sub>4</sub>:Bi<sup>3+</sup>
ECS journal of solid state science and technology