'designed/made/retailed by'
The item is by the architect, designer, maker or retailer.

'attributed to'
In our opinion the item is by the named architect, designer, maker or retailer but less certainty is expressed than the preceeding statement

'after the design by'
In our opinion the item has been made following published designs by the named architect or designer where the architect/designer has not stated a maker at the time of publishing and where the publication was available to a wide audience of makers.

'in the style of'
In our opinion the item shares stylistic characteristics with known items by architects, designers, makers or retailers.