292 CAROTENOID CARBOXYLIC ACIDS XIII 



51. R. KuHN and L. Ehmann, Helv. chim. Acta 12 (1929) 904. 



52. J. F. B. VAN Hasselt, Rec. Trav. chim. Pays-Bas 30 (191 1) 31. 



53. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 754. — Cf. R. Kuhn and A. 

 WiNTERSTEiN, Ber. 65 (1932) 650. 



54. R. PuMMERER, L. Rebmann and W. Reindel, Ber. 62 (1929) 1417. 



55. F. Viebock, Ber. 6y (1934) 377- 



56. P. Karrer and co-workers, Helv. chim. Acta 15 (1932) 1417. 



57. A. Heiduschka and H. Riffart, Arch. Pharm. 249 (191 1) 43. — J. F. B. van 

 Hasselt, Rec. Trav. chim. Pays-Bas 30 (191 1) 26. 



58'. C. Liebermann and G. Muhle, Ber. 48 (1915) 1657. 



59. A. Heiduschka and H. Riffart, Arch. Pharm. 24g (1911) 43. 



60. J. F. B. van Hasselt, Rec. Trav. chim. Pays-Bas 30 (191 1) 17. 



61. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 750. 



62. B. V. EuLER, H. v. EuLER and P. Karrer, Helv. chim. Acta 12 (1929) 278. 



63. R. Kuhn and co-workers, Helv. chim. Acta 11 (1928) 723. 



64. L. MARCHLEWSKiandL. Matejko.^w^. Akad.Wiss.Krakau.igo^, 749 (C. 1906,11, 1265). 



65. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 748, 755. 



66. R. Kuhn and A. Winterstein, Ber. 65 (1932) 650. 



67. J. Herzig and F. Faltis, Ann. 431 (1923) 49. — Cf. R. Kuhn and co-workers, Helv. 

 chim. Acta 11 (1928) 723; 12 (1929) 910. 



68. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 749. 



69. J. F. B. VAN Hasselt, Rec. Trav. chim. Pays-Bas 30 (191 1) 8. 



70. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 751. 



71. J. Herzig and F. Faltis, Ann. 431 (1923) 61. 



72. K. W. Hausser and A. Smakula, Z. angew. Chem. 4j (1934) 662; A. Smakula, Z. 

 angew. Chem. 48 (1935) I52- 



73. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 753. — R. Kuhn and A. 

 Winterstein, Ber. 65 (1932) 650. 



74. I. J. Rinkes, Chem. Centr. 1916, I, 336. — I. J. Rinkes and J. F. B. van Hasselt, 

 Chem. Centr. igiy, I, 208, II, 680. — R. Kuhn, A. Winterstein and L. Karlovitz, 

 Helv. chim. Acta 12 (1929) 66. — I. J. Rinkes and J. F. B. van Hasselt, Chem. Centr. 

 1916, II, 390; Chem. Centr. igiy, I, 208, II, 680. — I. J. Rinkes, Rec. Trav. chim. 

 Pays-Bas 48 (1929) 1093. 



75. R. Kuhn and A. Winterstein, Ber. 65 (1932) 650. 



76. P. Karrer and T. Takahashi, Helv. chim. Acta 16 (1933) 288. 



77. R. Kuhn and A. Winterstein, Ber. 63 (1932) 650. 



78. R. Kuhn and co-workers, Ber. 65 (1932) 1459, 1785. 



79. J. Herzig and F. Faltis, Ann. 431 (1923) 48. 



80. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 751. 



81. R. Kuhn and L. Ehmann, Helv. chim. Acta 12 (1929) 905. 



82. R. Kuhn and L. Ehmann, Helv. chim. Acta 12 (1929) 905. — P. Karrer and co- 

 workers, Helv. chim. Acta 15 (1932) 1406. 



83. P. Karrer and co-workers, Helv. chim. Acta 15 (1932) 1404. 



84. F. Faltis and F. Viebock, Ber. 62 (1929) 706. — P. Karrer and co-workers, Helv. 

 chim. Acta 12 (1929) 750; 75 (1932) 1416. 



85. P. Karrer and co-workers, Helv. chim. Acta 75 (1932) 141 7. 



86. J. F. B. van Hasselt, Rec. Trav. chim. Pays-Bas 30 (1911) 13. 



87. J. F. B. van Hasselt, Chem. Weekbl. 6 (1909) 482; Rec. Trav. chim. Pays-Bas 30 

 (1911) 14. 



88. J. F. B. van Hasselt, Rec. Trav. chim. Pays-Bas 30 (1911) 13. 



89. A. Oswald, Dissertation, Ziirich 1939. 



90. P. Karrer and F. Rubel, Helv. chim. Acta ly (1934) 773. 



91. P. Karrer and U. Solmssen, Helv. chim. Acta 20 (1937) 1396. 



92. P. Karrer and U. Solmssen, Helv. chim. Acta 20 (1937) i396- 



93. Aschoff, Ber. Jb. 51 (1818) 142. 



