msg 207, Invalid column name, sql 2008

hi every body

could you please tell me what is the below problem?!

SELECT [customer-grp].name as [group] ,[city-customer].name as city, 
		customer.pk, customer.name as customer ,
		customer.[address] ,[tel-customer].tel 
		FROM dbo.[customer] JOIN dbo.[city-customer]
		ON customer.[city-FK] = [city-customer].pk
		JOIN dbo.[customer-grp] 
		ON customer.[customerGrp-FK]= [customer-grp].pk 
		JOIN dbo.[tel-customer] 
		ON customer.pk  = [tel-customer].[customer-FK]
		GROUP BY [group], city,  customer.pk

امیدوارم همیشه بروز باشید I hope always be up2date