checkCIF procedure

PLAT860

 The use of restraints used in the refinement should be explained in
 the write-up of a structure analysis.  
 It is also recommended to include the refinement instructions in the   
 CIF (e.g. the final .res of a SHELXL refinement) as a comment: 
 _iucr_refine_instructions_details  
 ;  
 TITL   
 .. 
 (etc.) 
 ;  
 NOTE: An exception are restraints for floating origins (e.g. in P21).