Merge pull request #360 from aidancuckoo/patch-2

Update pca10056.md

Author: tannewt

_board/pca10056.md

@@ -13,7 +13,16 @@ features:
 The Nordic nRF52840 kit is hardware compatible with the Arduino Uno Revision 3 standard for shields, making it possible to use 3rd-party shields that are compatible to this standard. An NFC antenna can be connected the kit to enable NFC tag functionality. The kit gives access to all I/O and interfaces via connectors and has 4 LEDs and 4 buttons which are user-programmable. It supports the standard Nordic Software Development Tool-chain using Segger Embedded Studio, Keil, IAR and GCC. Program/Debug options on the kit is Segger J-Link OB.
 
 ## Purchase
-* [Comparison](https://www.nordicsemi.com/About-us/BuyOnline?search_token=nrf52840-DK)
+* [Price Comparison](https://www.nordicsemi.com/About-us/BuyOnline?search_token=nrf52840-DK)
+* [Arrow Electronics](https://www.arrow.com/en/products/nrf52840-dk/nordic-semiconductor?utm_source=oemsecrets&utm_medium=aggregator&utm_campaign=oemsecrets_2019_arrow&utm_content=inv_listing&utm_keyword=NRF52840-DK)
+* [Symmetry Electronics](https://www.semiconductorstore.com/cart/pc/viewPrd.asp?idproduct=94949&utm_source=OemSecrets&utm_medium=compref&utm_campaign=OemSecrets&utm_term=NRF52840-DK)
+* [Mouser](https://www.mouser.co.uk/ProductDetail/Nordic-Semiconductor/nRF52840-DK?qs=F5EMLAvA7IA76ZLjlwrwMw==&utm_source=OEMSECRETS&utm_medium=aggregator&utm_campaign=nRF52840-DK&utm_term=nrf52840-DK&utm_content=Nordic%20Semiconductor)
+* [Digi-Key](https://www.digikey.com/product-detail/en/nordic-semiconductor-asa/NRF52840-DK/1490-1072-ND/8593726?utm_source=oemsecrets&utm_medium=aggregator&utm_campaign=buynow)
+* [Avnet America](https://www.avnet.com/shop/us/products/nordic-semiconductor/nrf52840-dk-3074457345635668705?CMP=EMA_OEMSecrets_inventoryfeed_VSE)
+* [Farnell](https://sg.element14.com/nordic-semiconductor/nrf52840-dk/dev-kit-bluetooth-low-energy-soc/dp/2842321?CMP=GRHB-OEMSECRETS)
+* [Avnet Europe/Middle East/Africa](https://www.avnet.com/shop/emea/products/nordic-semiconductor/nrf52840-dk-3074457345635159181?c=EUR&r=EMEA&CMP=EMEA_OEMSecrets_inventoryfeed_VSE)
+* [TME](https://www.tme.eu/en/details/nrf52840-dk/development-kits-others/nordic-semiconductor/?utm_source=oemsecrets.com&utm_medium=cpc&utm_campaign=compare-2020-01)
+* [Avnet Asia Pacific](https://www.avnet.com/shop/apac/products/nordic-semiconductor/nrf52840-dk-3074457345635203852?r=ASIA&CMP=ASIA_OEMSecrets_inventoryfeed_VSE)
 
 ## Contribute