| Agent-based Integrated Assessment Models: Alternative Foundations to the Environment-Energy-Economics Nexus Karl Naumann-Woleske | L4–5 Advanced | CC-BY-SA | mirrored | 33 pp. | arxiv |
| Agent Simulation of Chain Bankruptcy Yuichi Ikeda, Yoshi Fujiwara, Wataru Souma | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| A Guide to Physical Activity (Kramer) Eydie Kramer | L1–3 Foundational | CC-BY | link only | — | libretexts |
| A Guide to the Gothic Jeanette A Laredo | L1–3 Foundational | CC-BY | link only | — | libretexts |
| A Guide to the Principles of Animal Nutrition Gita Cherian | L1–3 Foundational | CC-BY-NC | mirrored | 120 pp. | libretexts |
| A housing-demographic multi-layered nonlinear model to test regulation strategies Ramon Huerta, Fernando Corbacho, Luis F. Lago-Fernandez | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| A Laboratory Guide to Clinical Hematology (Villatoro and To) Valentin Villatoro, Michelle To | L1–3 Foundational | CC-BY-NC | mirrored | 206 pp. | libretexts |
| Algebra 1 | L1–2 Foundational | CC-BY-NC-SA | mirrored | 1,535 pp. | openstax |
| Algebra and Trigonometry | L1–2 Foundational | CC-BY | mirrored | 1,220 pp. | openstax |
| Algebra and Trigonometry 2e | L1–2 Foundational | CC-BY-NC-SA | mirrored | 1,467 pp. | openstax |
| Algorithmic Complexity in Real Financial Markets R. Mansilla | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Algorithmic Writing Assistance on Jobseekers' Resumes Increases Hires Emma van Inwegen, Zanele Munyikwa, John J. Horton | L4–5 Advanced | CC-BY | mirrored | 41 pp. | arxiv |
| All Are Welcome: An Introduction to the Hospitality Industry Christy Douglass et al. | L1–3 Foundational | CC-BY-NC | mirrored | 286 pp. | libretexts |
| A Look at Financial Dependencies by Means of Econophysics and Financial Economics M. Raddant, T. Di Matteo | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| A mathematical framework for modelling order book dynamics Rama Cont, Pierre Degond, Lifan Xuan | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| A Mechanism for Pockets of Predictability in Complex Adaptive Systems Jorgen Vitting Andersen, Didier Sornette | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| American Government | L1–2 Foundational | CC-BY | mirrored | 778 pp. | openstax |
| American Government 2e | L1–2 Foundational | CC-BY | mirrored | 781 pp. | openstax |
| American Government 3e | L1–2 Foundational | CC-BY | mirrored | 726 pp. | openstax |
| American Government 4e | L1–2 Foundational | CC-BY-NC-SA | mirrored | 737 pp. | openstax |
| American Literature I Anne Eidenmuller | L1–3 Foundational | CC-BY-SA | mirrored | 355 pp. | libretexts |
| American Options under Proportional Transaction Costs: Pricing, Hedging and Stopping Algorithms for Long and Short Positions Alet Roux, Tomasz Zastawniak | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| A Miniguide to Critical Thinking Joe Y. F. Lau | L1–3 Foundational | CC-BY-NC-SA | link only | — | libretexts |
| A Mixed Course Based Research Approach to Human Physiology Karri Haen Whitmer | L1–3 Foundational | CC-BY-SA | link only | — | libretexts |
| A Model for Counterparty Risk with Geometric Attenuation Effect and the Valuation of CDS Yunfen Bai (1, 2), Xinhua Hu (1) | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| A model for interevent times with long tails and multifractality in human communications: An application to financial trading J. Perello, J. Masoliver, A. Kasprzak | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| A model of the term structure of interest rates based on L\'evy fields Sergio Albeverio, Eugene Lytvynov, Andrea Mahnig | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| A multi-time scale non-Gaussian model of stock returns Lisa Borland | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| A multivariate multifractal model for return fluctuations E. Bacry (1) J. Delour (2) J.F. Muzy (2, 3) ((1) CMAP, Ecole Polytechnique Palaiseau France (2) CRPP | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| An Adaptive Method for Valuing an Option on Assets with Uncertainty in Volatility Sergei Fedotov, Stephanos Panayides | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| An adaptive splitting method for the Cox-Ingersoll-Ross process C\'onall Kelly, Gabriel J. Lord | L4–5 Advanced | CC-BY | mirrored | 29 pp. | arxiv |
| Analysing tax evasion dynamics via the Ising model Georg Zaklan, Frank Westerhoff, Dietrich Stauffer | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Analysis of delay correlation matrices K. B. K. Mayya, R. E. Amritkar | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Analytical modelling of terminal properties in industrial growth Arnabi Marjit, Sudipto Marjit, Arnab K. Ray | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Analytic RFR Option Pricing with Smile and Skew Colin Turfus, Aurelio Romero-Berm\'udez | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Analyzing Linear DSGE models: the Method of Undetermined Markov States Jordan Roulleau-Pasdeloup | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Anatomical Illustrations (Most, Tran, Seweryn, and Graham) Corrina Most, Katherine Tran, Olivia Seweryn | L1–3 Foundational | CC-BY-NC-SA-3.0 | link only | — | libretexts |
| Anatomy and Physiology | L1–2 Foundational | CC-BY | mirrored | 1,420 pp. | openstax |
| Anatomy and Physiology OpenStax | L1–3 Foundational | CC-BY | link only | — | libretexts |
| Anatomy and Physiology 2e | L1–2 Foundational | CC-BY-NC-SA | mirrored | 1,347 pp. | openstax |
| Anatomy and Physiology (Boundless) | L1–3 Foundational | CC-BY-SA | link only | — | libretexts |
| Anatomy and Physiology II Laboratory Manual Sheryl Shook | L1–3 Foundational | CC-BY | link only | — | libretexts |
| Anatomy and Physiology of Animals Ruth Lawson | L1–3 Foundational | CC-BY-SA-3.0 | mirrored | 407 pp. | libretexts |
| An Economic Model of Coupled Exponential Maps R. Lopez-Ruiz, J. Gonzalez-Estevez, M.G. Cosenza | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| An Efficient Algorithm for Optimal Routing Through Constant Function Market Makers Theo Diamandis, Max Resnick, Tarun Chitra | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| An EKG Interpretation Primer Jacqueline Christianson et al. | L1–3 Foundational | CC-BY-NC-SA | mirrored | 49 pp. | libretexts |
| An Ellsberg paradox for ambiguity aversion Christoph Kuzmics, Brian W. Rogers, Xiannong Zhang | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| An empirical behavioral model of liquidity and volatility Szabolcs Mike, J. Doyne Farmer | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| An Enquiry Concerning Human Understanding Hume, David | L2–5 Introductory | Public domain | mirrored | — | gutenberg |
| An equilibrium model for matching impatient demand and patient supply over time Garud Iyengar, Anuj Kumar | L4–5 Advanced | Licence unknown | link only | — | arxiv |