# Sources Overview

Sources are where works are hosted: journals, conferences, preprint repositories, and institutional repositories.

## Filter, sort, and group_by fields

The API supports filtering, sorting, and grouping on sources fields. See [Filtering](/api/filtering/), [Sorting](/api/sorting/), and [Grouping](/api/grouping/) for syntax.

Fields marked **(deprecated)** are `.search` filters — use the [`search` parameter](/api/searching/) instead.

### Top-level

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `apc_usd` | ✓ | ✓ | ✓ |
| `cited_by_count` | ✓ | ✓ | ✓ |
| `continent` | ✓ | ✓ | ✓ |
| `country_code` | ✓ | ✓ | ✓ |
| `display_name` | ✓ |  | ✓ |
| `first_publication_year` | ✓ |  | ✓ |
| `from_created_date` | ✓ |  | ✓ |
| `has_issn` | ✓ | ✓ | ✓ |
| `host_organization` | ✓ | ✓ | ✓ |
| `host_organization_lineage` | ✓ | ✓ | ✓ |
| `is_core` | ✓ | ✓ | ✓ |
| `is_global_south` | ✓ | ✓ | ✓ |
| `is_high_oa_rate` | ✓ | ✓ | ✓ |
| `is_high_oa_rate_since_year` | ✓ |  | ✓ |
| `is_in_doaj` | ✓ | ✓ | ✓ |
| `is_in_doaj_since_year` | ✓ |  | ✓ |
| `is_in_jstage` |  | ✓ | ✓ |
| `is_in_jstage_since_year` |  |  | ✓ |
| `is_oa` | ✓ | ✓ | ✓ |
| `is_ojs` | ✓ | ✓ | ✓ |
| `issn` | ✓ | ✓ | ✓ |
| `issn_l` | ✓ | ✓ | ✓ |
| `last_publication_year` | ✓ |  | ✓ |
| `oa_flip_year` | ✓ |  | ✓ |
| `openalex` | ✓ | ✓ | ✓ |
| `openalex_id` |  | ✓ | ✓ |
| `to_created_date` | ✓ |  | ✓ |
| `to_updated_date` | ✓ |  | ✓ |
| `type` | ✓ | ✓ | ✓ |
| `works_count` | ✓ | ✓ | ✓ |

### Apc Prices

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `apc_prices.currency` | ✓ | ✓ | ✓ |
| `apc_prices.price` | ✓ |  | ✓ |

### Concept

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `concept.id` | ✓ | ✓ | ✓ |

### Concepts

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `concepts.id` | ✓ | ✓ | ✓ |

### Default

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `default.search` **(deprecated)** |  |  | ✓ |

### Display Name

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `display_name.search` **(deprecated)** |  |  | ✓ |

### Host Organization

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `host_organization.id` | ✓ |  | ✓ |

### Ids

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `ids.mag` | ✓ |  | ✓ |
| `ids.openalex` | ✓ | ✓ | ✓ |

### Summary Stats

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `summary_stats.2yr_mean_citedness` | ✓ | ✓ | ✓ |
| `summary_stats.h_index` | ✓ | ✓ | ✓ |
| `summary_stats.i10_index` | ✓ | ✓ | ✓ |

### Topic Share

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `topic_share.id` | ✓ | ✓ | ✓ |

### Topics

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `topics.id` |  |  | ✓ |

### X Concepts

| Field | Sort | Group_by | Filter |
|-------|:----:|:--------:|:------:|
| `x_concepts.id` | ✓ | ✓ | ✓ |