Fix typo

Author: nopara73

bitcoin_transfer/transaction.md

@@ -17,7 +17,7 @@ For now we are interested in the **Transaction ID**. In this case, it is ```f13d
 You can review the transaction on a blockexplorer like Blockchain.info: https://blockchain.info/tx/f13dc48fb035bbf0a6e989a26b3ecb57b84f85e0836e777d6edf60d87a4a2d94 
 But as a developer you will probably want a service that is easier to query and parse.  
 As a C# developer and an NBitcoin user Nicolas Dorier's [QBit Ninja](http://docs.qbitninja.apiary.io/) will definitely be your best choice. It is an open source web service API to query the blockchain and for tracking wallets.  
-QBit Ninja depends on [NBitcoin.Indexer](https://github.com/MetacoSA/NBitcoin.Indexer) which relies on Microsoft Azure Storage. C# developers are expected to use the [NuGet client package](http://www.nuget.org/packages/QBitninja.Client) instead of developping a wrapper around this API.  
+QBit Ninja depends on [NBitcoin.Indexer](https://github.com/MetacoSA/NBitcoin.Indexer) which relies on Microsoft Azure Storage. C# developers are expected to use the [NuGet client package](http://www.nuget.org/packages/QBitninja.Client) instead of developing a wrapper around this API.  
 
 If you go to http://api.qbit.ninja/transactions/f13dc48fb035bbf0a6e989a26b3ecb57b84f85e0836e777d6edf60d87a4a2d94 you will see the raw bytes of your transaction.