Keywords: Quasars; Gravitational Lensing; Double Quasars

1. INTRODUCTION

2. BUILDING THE CANDIDATE SAMPLE

2.1. Data Sets

2.2. Candidate Selection

3. FOLLOW-UP OBSERVATIONS

4. J0025–0145: AN INTERMEDIATELY-LENSED QUASAR AT $Z=5.07$

6. LOW-REDSHIFT LENSED QUASARS AND QUASAR PAIRS

7. DISCUSSIONS AND FUTURE WORK

8. SUMMARY