1 INTRODUCTION

2 DATA
2.1 Submm
2.2 Radio and mid-infrared
2.3 Optical and near-infrared

3 GALAXY IDENTIFICATIONS

4 COMPARISON WITH ALMA FOLLOW-UP
4.1 Validation of galaxy identifications
4.2 Multiplicity and number counts

5 LONG-WAVELENGTH PHOTOMETRY

6 REDSHIFTS AND NUMBER DENSITY

7 STAR FORMATION RATES AND STELLAR MASSES

8 DISCUSSION: EXTREME STAR FORMATION IN THE UNIVERSE
8.1 Main-sequence nature and the maximum SFR
8.2 Submm galaxies without IDs
8.3 Submm galaxies in cosmological context

9 CONCLUSIONS