| Roof Structures, Ancient Greece |
ARC 860 |
| Roof Structures, Ancient Rome |
ARC 878 |
| Roof Trusses |
BAU 482 |
| Roof Trusses for Wide Spans, Timber Construction |
BAU 481 |
| Roof-Gardens |
LAN 492 |
| Roofing Tiles |
BAU 328 |
| Roofs |
ARC 428 |
| Roofs, Timber Construction |
BAU 491 |
| Room Protection Systems |
MSR 936 |
| Root Crops |
LAN 350 |
| Root Vegetable Crops |
LAN 434 |
| Roots |
LAN 350 |
| Rope Bridges |
BAU 730 |
| Rope Drives |
MAS 326 |
| Ropemaking |
IND 715 |
| Ropes, Statics |
MTA 110 |
| Ropeyard |
IND 715 |
| Rosidae |
BIO 563 |
| Rotary (Screw) Compressors |
MAS 662 |
| Rotary Alternating Current Drives / Propulsion Units |
ELT 840 |
| Rotary Alternating Current Machines |
ELT 840 |
| Rotary Compressors |
MAS 658 |
| Rotary Cranes |
MAS 727 |
| Rotary Machine |
IND 969 |
| Rotary Piston Compressors |
MAS 662 |
| Rotary Piston Engines |
MAS 529 |
| Rotary Piston Machines |
MAS 529 |
| Rotary-Wing Aircraft |
VER 562 |
| Rotating Flow |
PHY 225 |
| Rotating Objects |
MTA 270 |
| Rotation Ellipsoids, Geodesy |
BAU 943 |
| Rotation-Symmetrical Shells |
BAU 184 |
| Rotation, Earth, Fluctuations |
GEO 505 |
| Rotational Frequency Measurement |
MSR 326 |
| Rotational Speed, Control |
MSR 882 |
| Rotodynamic Pumps |
MAS 625 |
| Rotor, Kinetics |
MTA 270 |
| Rotor, Turbine |
MAS 573 |
| Roundworms |
BIO 816 |
| Rowing |
SPO 325 |
| RStV |
JUR 783 |
| Rubber |
WER 670 |
| Rubber Springs |
MAS 176 |
| Rubber Technology |
CIT 760 |
| Rubidium |
CHE 362 |
| Rubidium |
WER 318 |
| Rugby |
SPO 457 |
| Ruhr Area, Local Planning Community |
RPL 406 |
| Ruhr Area, Statistics for Regional Planning |
RPL 968 |
| Ruhr, Regional Planning Authority |
RPL 403 |