diff --git a/docs/product/genre-packs/SOURCES.md b/docs/product/genre-packs/SOURCES.md
new file mode 100644
index 0000000..453b5b7
--- /dev/null
+++ b/docs/product/genre-packs/SOURCES.md
@@ -0,0 +1,50 @@
+# Core 3 — source URLs (save & reuse)
+
+Canonical links for Discovery foundation / field-map work. **Do not invent fields from memory — open these.**  
+If a link is dead or gated, mark **BLOCKED** in chat and in `core3-field-map.md`.
+
+Last updated: 2026-09-15 (porbot)
+
+---
+
+## GBP (Google Business Profile)
+
+| What | URL |
+| :--- | :--- |
+| Business Information API (REST index) | https://developers.google.com/my-business/reference/businessinformation/rest |
+| Location resource (field names: `title`, `storefrontAddress`, `phoneNumbers`, `websiteUri`, `regularHours`, `specialHours`, `serviceArea`, `profile`, `serviceItems`, …) | https://developers.google.com/my-business/reference/businessinformation/rest/v1/locations |
+| Work with location data (howto) | https://developers.google.com/my-business/content/location-data |
+| Manage attributes (howto) | https://developers.google.com/my-business/content/attributes |
+| `attributes.list` method | https://developers.google.com/my-business/reference/businessinformation/rest/v1/attributes/list |
+| Place Actions API (related — booking/order links) | https://developers.google.com/my-business/content/basic-setup (enable Place Actions among GBP APIs) |
+
+---
+
+## Apple Business Connect
+
+| What | URL |
+| :--- | :--- |
+| Apple Business user guide (index / crawl root) | https://support.apple.com/guide/business/welcome/web |
+| Configure location attributes (owner-facing field labels) | https://support.apple.com/guide/business/configure-location-attributes-abcbdc543423/web |
+| Brand identity attributes (brand-level — not Location schema) | https://support.apple.com/guide/business/brand-identity-attributes-abcbb1973199/web |
+
+**BLOCKED:** Apple Business Connect Location API data specification (camelCase resource fields), e.g. `https://businessconnect.apple.com/docs/data-specification/v1.3/…` — often partner-gated; do not invent names. Unlock: accessible dump or paste of Location resource.
+
+---
+
+## Bing Places
+
+| What | URL |
+| :--- | :--- |
+| Bing Places for Business API docs (PDF, “Latest”) | https://cdn.bingplaces.com/tpshared/BingPlaces_API_Latest.pdf |
+| Bing Places for Business API docs (PDF, v1.0 mirror) | https://bpprodpublicstorage.blob.core.windows.net/bingplacesapi/BingPlaces_API_v1.0.pdf |
+
+**Note:** Bing Places partner API is **trusted-partner / certificate** access, not a public directory crawl API. Field names in our map come from that PDF family; if PDF moves, re-verify before editing the field map.
+
+---
+
+## How we use this
+
+1. Field map SoT: [`core3-field-map.md`](./core3-field-map.md)  
+2. Genre application: [`salon.md`](./salon.md), [`bakery.md`](./bakery.md)  
+3. New platform docs → add URL here first, then update the field map from the page (never from memory).
diff --git a/docs/product/genre-packs/core3-field-map.md b/docs/product/genre-packs/core3-field-map.md
index cd975ac..0b36947 100644
--- a/docs/product/genre-packs/core3-field-map.md
+++ b/docs/product/genre-packs/core3-field-map.md
@@ -4,10 +4,10 @@
 **Rule:** never invent platform fields. Attributes for a genre = only after live `attributes.list` (GBP) / Good to Know enums (Apple) for that category + country.  
 **Process:** if blocked, say **BLOCKED** (what’s missing / why / unlock) — no paint-overs.
 
-**Sources (2026-09-15):**
-- GBP Location API + Attributes API
-- Apple Business user guide — [Configure location attributes](https://support.apple.com/guide/business/configure-location-attributes-abcbdc543423/web) (via [Welcome](https://support.apple.com/guide/business/welcome/web))
-- Bing Places API documentation
+**Sources:** see [`SOURCES.md`](./SOURCES.md) (GBP / Apple / Bing URLs). Snapshot:
+- GBP: [Location resource](https://developers.google.com/my-business/reference/businessinformation/rest/v1/locations), [`attributes.list`](https://developers.google.com/my-business/reference/businessinformation/rest/v1/attributes/list)
+- Apple: [Welcome](https://support.apple.com/guide/business/welcome/web) → [Configure location attributes](https://support.apple.com/guide/business/configure-location-attributes-abcbdc543423/web)
+- Bing: [Places API PDF (Latest)](https://cdn.bingplaces.com/tpshared/BingPlaces_API_Latest.pdf)
 
 **Apple naming:** owner-facing **UI labels** from Configure location attributes (below). Still **BLOCKED** on separate camelCase Location API resource names from `businessconnect.apple.com` data-spec v1.3 until that dump is available — we do not invent them.