| Abbreviation | Definition |
|---|---|
| HPLD | Havana Public Library District |
| HPLD | High Plains Library District |
| HPM | Hand Printed Multiple |
| HPPL | High Point Public Library |
| HPPL | Highland Park Public Library |
| HQO | HeritageQuest Online |
| HSDL | Homeland Security Digital Library |
| HSL | Health Sciences Libraries |
| HSLS | Health Sciences Library System |
| HSML | Harry Simpson Memorial Library |
| HSML | History of Science and Medicine Library |
| HSNL | HEIS Sample Number Library |
| HSSL | Humanities and Social Sciences Library |
| htc | Harvard Theatre Collection |
| HTL | Histogram Template Library |
| HTL | HTML Template Library |
| HUA | Harvard University Archives |
| HUL | Harvard University Library |
| HUL | Helsinki University Library |
| HumToxicol | Human Toxicology (England) |