768 - Citation and Preference Order Instructions (R)
      
      MARC 21 Classification - Concise
      
         					2008
         				
      
      
      Note or table with instructions about the order in which elements are to be applied in
         synthesizing a classification number or instructions about preference for the
              classification of different characteristics of a topic.
      
      Indicators
      First - Type of instruction
         
0 - Citation and preference order note
         1 - Table of preference
       
      Second - Undefined
         
# - Undefined
       
      Subfield Codes
      $a - Classification number-Single number or beginning number of span (R)
      $c - Classification number-Ending number of span (R)
      $e - Example class number (R)
      $i - Explanatory text (R)
      $j - Caption (R)
         
Caption for the immediately following classification number in a table of
                              preference. This caption usually matches the caption in field 153 (Classification
                              Number) for that classification number.
         
       
      $n - Negative example class number (R)
         
Example of the incorrect classification number for the topic used to illustrate
                              the citation and preference order instruction.
         
       
      $t - Topic used as example of citation and preference order instruction (R)
      $x - Exception to table of preference (R)
      
         $y - Table sequence number for internal subarrangement or add table (R)
      
      $z - Table identification-Table number (R)
      
      $8 - Field link and sequence number (NR)
         
       
      Examples
      
         
            
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               | 768 | 
               0#$81.1$iGive priority in notation to the continent, country,
                                       locality emphasized. If emphasis is equal, give priority to the one coming
                                       first in Table 2
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               | 768 | 
               0#$iObserve table of preference under$a800
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               | 768 | 
               0#$iUnless other instructions are given, class a subject with
                                       aspects in two or more subdivisions of$a641.563$iin the number coming first, e.g.,$tlow-carbohydrate, low-calorie cooking for persons with
                                       diabetes$e641.56314$i(not$n641.5635$ior$n 641.5638)
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               | 768 | 
               1#$81.3$jLabor force by personal characteristics$a331.3$c331.6
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               | 768 | 
               1#$81.7$jLabor by industry and occupation$a331.7$x(except$a331.702) | 
            
        
            
               | 768 | 
               1#$81.1$iUnless other instructions are given, observe the following
                                       table of preference, e.g.,$tlanguage and communication in education and research$z1$e07$i(not$z1$n014):
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               | 768 | 
               1#$81.2$jSpecial topics$z1$a04
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               | 768 | 
               1#$81.7$jManagement$z1$a068
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               | 768 | 
               1#$81.16$jTreatment by specific continents, countries, localities;
                                       extraterrestrial worlds$z1$a093$c099....
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