update dataset card

README.md

@@ -91,6 +91,7 @@ configs:
 <div align="center">
 
 [![huggingface](https://img.shields.io/badge/%F0%9F%A4%97-Hugging_Face_Collections-yellow)](https://huggingface.co/collections/w11wo/massive-steps-point-of-interest-check-in-dataset-67edf6dbb60e30eac9a9af1b)
+[![arXiv](https://img.shields.io/badge/arXiv-2505.11239-b31b1b.svg)](https://arxiv.org/abs/2505.11239)
 [![GitHub](https://img.shields.io/badge/github-%23121011.svg?logo=github&logoColor=white)](https://github.com/w11wo/Massive-STEPS)
 
 </div>
@@ -191,6 +192,22 @@ Unless required by applicable law or agreed to in writing, software distributed
 See the License for the specific language governing permissions and limitations under the License.
 ```
 
+## 🔖 Citation
+
+If you find this repository useful for your research, please consider citing our paper:
+
+```bibtex
+@misc{wongso2025massivestepsmassivesemantictrajectories,
+  title         = {Massive-STEPS: Massive Semantic Trajectories for Understanding POI Check-ins -- Dataset and Benchmarks},
+  author        = {Wilson Wongso and Hao Xue and Flora D. Salim},
+  year          = {2025},
+  eprint        = {2505.11239},
+  archiveprefix = {arXiv},
+  primaryclass  = {cs.LG},
+  url           = {https://arxiv.org/abs/2505.11239}
+}
+```
+
 ### Contact
 
 If you have any questions or suggestions, feel free to contact Wilson at `w.wongso(at)unsw(dot)edu(dot)au`.