@inproceedings{pme336559-macmillanpitsandpilesd,
  title={Pits and Piles, Directions, and Debt: Pre-service Teachers' Conceptions of Negative Numbers},
  author={Macmillan, Emily and Ingram, Jenni},
  booktitle={Proceedings of the International Group for the Psychology of Mathematics Education, Volume 1},
  year={2026},
  pages={963--970},
  publisher={Psychology of Mathematics Education (PME)},
  issn={2790-3648}
}