APA (7th ed.) Citation

Köhli, P., Hambrecht, J., Zhu, J., Chiapparelli, E., Guven, A., Tsuchiya, K., . . . Hughes, A. Seasonal variations of preoperative vitamin D deficiency and secondary hyperparathyroidism before lumbar fusion surgery. Elsevier.

Chicago Style (17th ed.) Citation

Köhli, P., et al. Seasonal Variations of Preoperative Vitamin D Deficiency and Secondary Hyperparathyroidism Before Lumbar Fusion Surgery. Elsevier.

MLA (9th ed.) Citation

Köhli, P., et al. Seasonal Variations of Preoperative Vitamin D Deficiency and Secondary Hyperparathyroidism Before Lumbar Fusion Surgery. Elsevier.

Warning: These citations may not always be 100% accurate.